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brought this up on another thread but got stifled by the Chewbacca Defense:

The warp is a terrible but necessary evil for all races in 40K......except for the Tau. How do the Tau communicate over the vast lightyears of space?

Pony express via messenger ships skipping off the discontinuity between reality and the Warp.

how's that work without psychics?

I don't think it is a problem for the Tau.

It's based off of the same idea as their movement throughout the Empire, the Tau Empire isn't very large in galactic terms so their short little puddle hopper jumps into the Warp isn't a problem in that they don't have very far to go.

I think the same can be said for their communication. Yes it takes a long time for standard non psychic messages to travel through space (at least for the Imperium it may be differant with Tau as their technology is more advanced) but the Tau Empire isn't that large so it may not be a problem.

Also keep in mind the Tau do have psykers in the form of floating
alien squids called the Nacissar (or however it's spelled).

KamikazeCanuck wrote:how's that work without psychics?

The Tau empire is small enough to rely upon technical solutions.
'interstellar' for a Tau, is just the close neighbourhood in Imperial terms.

Ya y'know close in interstellar terms is like 6 light years. That still means it takes 6 years for a non-psychic message to transmit.

I guess it is these Nicassar fellows. We know they're "highly psychic" but we don't know what they're doing for the Tau. However, they must be doing the long range communication for them. I did not know they were squids. Anyways, I wonder if they ever have problems of falling prey to Chaos.

The Tau have faster-than-light travel. Not as fast as full immersion in the Warp, but workable via gravitic manipulation, and apparently doesn't carry the risks of full immersion.

Nurglitch has it right. In the "A Tau'cyr Among the Kroot" section of the old Codex: Tau we learn that letters are carried between systems by message boats.

KamikazeCanuck wrote:how's that work without psychics?

While the Tau don't have Navigators, or indeed psykers of any flavour, they do have warp drives. They didn't develop it, but instead found a 'crashed' warp-capable ship on one of the moons within their home system.
When using the drive, the low psychic signature of the Tau mean that after entering the edge of the warp they are quickly forced out again, like a balloon being held underwater. This limits them to short hops, skimming the surface of the warp. A slower, but safer, method of travel than the ships of the Imperium.

Warboss Imbad Ironskull wrote:Also keep in mind the Tau do have psykers in the form of floating
alien squids called the Nacissar (or however it's spelled).

The Nicassar are a race of telekinetics. They move their ships through real-space, not the warp, and they take many centuries to travel between systems, the crew surviving in a natural state of virtual hibernation. Nicassar ships are not at all warp capable, and, like Tau Orca gunships, must be attached to a larger, warp-capable, vessel to move at any decent paced
We have no evidence that the Nicassar assist the Tau by providing interstellar communication. And [citation needed] on the floating squid description.

I'm aware of their "Warp hopping" ship travel. But it's supposed to be 1/5th (i think) as fast as "normal" warptravel.
I thought the letter carrying message boats was a metaphor but its seems to be serious. Doesn't seem an empire of 100 worlds can be held together by post!

An 'empire' of multiple countries separated by oceans on this world was.

This is why the tau empire is so small. Radius of communications determines effective sphere of operations.

People keep thinking of 40k in the contemporary time frame. It's medieval Europe in space with laserguns.

I doubt that the Nicissar are messengers for the tau because they are constantly on the move. I mean, what good is a telephone that gets up and walks away? Maybe the tau have some other form of interstellar communication, I bet some other sc-fi series has some ideas for interstellar communication that would work for tau.

Æscholt wrote:Nurglitch has it right. In the "A Tau'cyr Among the Kroot" section of the old Codex: Tau we learn that letters are carried between systems by message boats.

KamikazeCanuck wrote:how's that work without psychics?

While the Tau don't have Navigators, or indeed psykers of any flavour, they do have warp drives. They didn't develop it, but instead found a 'crashed' warp-capable ship on one of the moons within their home system.
When using the drive, the low psychic signature of the Tau mean that after entering the edge of the warp they are quickly forced out again, like a balloon being held underwater. This limits them to short hops, skimming the surface of the warp. A slower, but safer, method of travel than the ships of the Imperium.

Warboss Imbad Ironskull wrote:Also keep in mind the Tau do have psykers in the form of floating
alien squids called the Nacissar (or however it's spelled).

The Nicassar are a race of telekinetics. They move their ships through real-space, not the warp, and they take many centuries to travel between systems, the crew surviving in a natural state of virtual hibernation. Nicassar ships are not at all warp capable, and, like Tau Orca gunships, must be attached to a larger, warp-capable, vessel to move at any decent paced
We have no evidence that the Nicassar assist the Tau by providing interstellar communication. And [citation needed] on the
floating squid description.

The instance of a Tau writing a letter can't be applied to the entire Tau Empire. Do you really think an empire as advanced as the Tau would really just send letters back and forth via messenger boats? I doubt it. Now yes I'm sure it's used it's even fluff but I doubt it is paper letters sealed in an envelope of some kind and sent off. More likely it is a datta slate or the Tau version of an email.

And itt could be that those "messenger ships" are ships designed to carry an advanced relay device for sending messages, it recieves the messages then sends them off to whatever needs them. It could even be a relay station where ships are stationed at intervals throughout the empire and these messenger boats send the message from one ship to another untill it reaches it's destination. Even at that there are people who still write letters today it dosen't mean that it's our primary means of communication.

The Nicassar squid thing was just how I've always invisioned them so don't take that seriously . But you are wrong, the description of the race is that they are PSYCHIC not telekinetic. Since they are psychic this classifies them as psykers in the 40K universe which is why the Tau have kep their use hidden from the Imperium. And you're right there isn't any evidence saying that they've been used for interstellar communication but there also hasen't been anything saying that they haven't so arguing it is a mute point. And saying that the Tau woulden't make use of that asset is a poor assumption considering the races knack for using the most usefull traits of their allies.

While it has not been outright stated how the Tau communicate over long distances we can take what fluff we have on the Tau (highly advanced technologically) and their allied races (Nicissar who are psychic and can probably communicate the same way other psykers in 40K do) and come to the conclusion that they either A) Have developed a method of communicating technologically that is fairly fast especially compared to the Imperiums technology or B) they transmit messages via the Nicissar and that they don't simply use "messenger boats".

As far as why the Nicissar ships don't have warp space capabilities it could be because as a psychic race they don't use the Warp to travel as a means of avoiding corruption. The Eldar use the webway 1 because it is faster then warp travel and 2 because it is alot safer, the Eldar are an entirely psychic race and so are at a high risk while in the warp. If it applies to them it would apply to the Nicissar as well. Or heck maybe they haden't developed the correct means to do it technologicly. Either way wether their ships use Warp Space to travel or not is irrelevant for if they use it for communication as they are two differant things.

No, the way their ships travel is extremely relevant in terms of communications if they have no astrotelepathy. Likewise telekinesis is a form of psychic power.

More importantly, if you read the Battlefleet Gothic material on Tau FTL flight more closely, you'll find that the psychic weakness of the Tau does not interfere with entering the Warp. Instead it is the gravitic propulsion that fails to penetrate the 'surface' of the Warp, and which forces them to move in short hops.

It doesn't matter you need navigators to traverse the warp so it best that they don't go in.

Nurglitch wrote:No, the way their ships travel is extremely relevant in terms of communications if they have no astrotelepathy. Likewise telekinesis is a form of psychic power.

More importantly, if you read the Battlefleet Gothic material on Tau FTL flight more closely, you'll find that the psychic weakness of the Tau does not interfere with entering the Warp. Instead it is the gravitic propulsion that fails to penetrate the 'surface' of the Warp, and which forces them to move in short hops.

So your saying that a ship has to be able to enter the warp in order for it to also be able to send messages through it? did I understand that right because if I did that makes no sens what so ever.

The fluff for the Nicissar says that they are psychic which telekinesis is a psychic power you're right but if they where limited to being only telekinetic then they would have been listed as telekinetic instead of psychic. If their powers where only limited to moving things with their minds then GW would have said so by giving them the correct lable.

No, you failed to understand that correctly. I'm saying that the ship carries the message. As in, message is transmitted to the ship electromagnetically, the ship skips off the surface of the Warp until it reaches its destination, and then transmits the message electromagnetically to its final destination.

^^ On the 'what do the nicassar look like', I believe GW has described them as 'a cross between a polar bear and a pancake'.

Nurglitch wrote:No, you failed to understand that correctly. I'm saying that the ship carries the message. As in, message is transmitted to the ship electromagnetically, the ship skips off the surface of the Warp until it reaches its destination, and then transmits the message electromagnetically to its final destination.

Yes but that's implying that that is how Tau communicate over long distances and there has never been anything of the sort even confirming that or as far as I know hinting at it. And frankly I think a race as technilogicly advanced as the Tau using that method is rediculous.

Go read the Battlefleet Gothic background on the Tau then.

Warboss Imbad Ironskull wrote:Yes but that's implying that that is how Tau communicate over long distances and there has never been anything of the sort even confirming that or as far as I know hinting at it. And frankly I think a race as technilogicly advanced as the Tau using that method is rediculous.

Not quite sure why its ridiculous, many SF settings have FTL travel without FTL communication, making courier ships or drones the standard means of communication.

Its particularly apt for 40k though, since as noted above its not modeled on the way the modern world operates.

Jack

If the Tau method of interstellar communication is mentioned in Battle Fleet Gothic why is this question unknown then? why is it that there are people who don't know how they do it if it's already covered and works the way it has been pruposed?

And yes many sci-fi settings do operate that way but the 40k setting is not the setting of every other (though certain elements are probably based off of others). I for one find it hard to believe that a race which went from flames and spears to space ships and galactic empires in the span of six thousand years uses ships to communicate in a pony express type manner.

Someone earlier said that it would work for the Tau because it worked for an empire in our history. Well that empire was limited to one planet and was technologically primitive in comparison to what the Tau are portrayed as in their fluff. If players want to believe that the Tau use messenger ships to jump from place to place and relay information they are perfectly welcome to it.

But I believe that a race as developed and ambitious as the Tau would have created a means of communicating that is more sophisticated and faster then "oh let's send a ship back and forth and hope they get there in time" and failing that they would use the psykers that they DO have to communicate.

The answer to the question is generally unknown because many people are like you in that all they seem to know about the background is what they read on forums and lexicanum, second-hand tripe in the main, and healthy lashings of ignorance.

Nurglitch wrote:The answer to the question is generally unknown because many people are like you in that all they seem to know about the background is what they read on forums and lexicanum, second-hand tripe in the main, and healthy lashings of ignorance.

Forgive me if the immaturity of that comment dosen't hurt my feelings. I hate to break it to you but those mass of people are a little more informed then you seem to think so before making statements like that you should really go back and read them and write them as if they are coming from a person who does not know everything or everyone. Just some freindly advice.

Give me a quoted cannon statement saying the exact method that Tau use to communicate at intersteller distances and if this supports what you say about messanger ships I will stand corrected and be informed on another aspect of the Taus fluff. But untill this is done I am perfectly entitled to my opinions and theories wether you like them or not, and if that puts me right alongside all those other players who you so boldly claim to be ignorant then so be it. I will be one of the many who do not know as much as you because there is no way that we have access to the vast amounts of fluff that you have. You are so above us lesser beings in your wisdom.

Warboss Imbad Ironskull wrote:

Æscholt wrote:Nurglitch has it right. In the "A Tau'cyr Among the Kroot" section of the old Codex: Tau we learn that letters are carried between systems by message boats.

KamikazeCanuck wrote:how's that work without psychics?

While the Tau don't have Navigators, or indeed psykers of any flavour, they do have warp drives. They didn't develop it, but instead found a 'crashed' warp-capable ship on one of the moons within their home system.
When using the drive, the low psychic signature of the Tau mean that after entering the edge of the warp they are quickly forced out again, like a balloon being held underwater. This limits them to short hops, skimming the surface of the warp. A slower, but safer, method of travel than the ships of the Imperium.

Warboss Imbad Ironskull wrote:Also keep in mind the Tau do have psykers in the form of floating
alien squids called the Nacissar (or however it's spelled).

The Nicassar are a race of telekinetics. They move their ships through real-space, not the warp, and they take many centuries to travel between systems, the crew surviving in a natural state of virtual hibernation. Nicassar ships are not at all warp capable, and, like Tau Orca gunships, must be attached to a larger, warp-capable, vessel to move at any decent paced
We have no evidence that the Nicassar assist the Tau by providing interstellar communication. And [citation needed] on the
floating squid description.

The Nicassar squid thing was just how I've always invisioned them so don't take that seriously . But you are wrong, the description of the race is that they are PSYCHIC not telekinetic. Since they are psychic this classifies them as psykers in the 40K universe which is why the Tau have kep their use hidden from the Imperium. And you're right there isn't any evidence saying that they've been used for interstellar communication but there also hasen't been anything saying that they haven't so arguing it is a mute point. And saying that the Tau woulden't make use of that asset is a poor assumption considering the races knack for using the most usefull traits of their allies.

While it has not been outright stated how the Tau communicate over long distances we can take what fluff we have on the Tau (highly advanced technologically) and their allied races (Nicissar who are psychic and can probably communicate the same way other psykers in 40K do) and come to the conclusion that they either A) Have developed a method of communicating technologically that is fairly fast especially compared to the Imperiums technology or B) they transmit messages via the Nicissar and that they don't simply use "messenger boats".

As far as why the Nicissar ships don't have warp space capabilities it could be because as a psychic race they don't use the Warp to travel as a means of avoiding corruption. The Eldar use the webway 1 because it is faster then warp travel and 2 because it is alot safer, the Eldar are an entirely psychic race and so are at a high risk while in the warp. If it applies to them it would apply to the Nicissar as well. Or heck maybe they haden't developed the correct means to do it technologicly. Either way wether their ships use Warp Space to travel or not is irrelevant for if they use it for communication as they are two differant things.

Hidden?

The Imperium is hunting psykers regularly, and thus able to find most of them. Maybe some very weak ones escape, but powerful psykers
are impossible to hide. Using the warp to communicate, allows to block comms, as we see with the Tyranids and occasionally at chaos incursions. If you want the Tau's comms intercepted and blocked, yes use the warp...

Option A)
Tech, should be the answer. Drones woul do fine, as would relay stations.

Option B)
No. Tau like their tech and would not rely upon strange methods of their vassals.

Plus, the webway isn't perfectly safe, if breached demons pour in and the Eldar had to close any gates endangered to be overrun.
Its fast and secure normally.

For clarity, if you put a letter in a ship which goes faster then light, you have a method of sending messages faster than light.

The question is whether this is fast enough for the communications needed to hold together a large organisation.

Communication isn't simply a matter of sending it quickly. The message must be composed, transmitted, received, understood and acted on. These things can often go wrong, delaying the effect of a message.

Case in point, I am working on a project with the PR department.

A couple of weeks ago I completed some stuff, sent it to them and requested a meeting to discuss it, which they agreed to. They then sent me an email asking for some changes.

I didn't read the email because it was buried in a mass of other emails, and because they had already told me they would present their requests at the already agreed meeting, so I wasn't really expecting a message from them.

The Monday of the meeting arrived and I found out the PR people had gone to a trade show for the whole week, so I put the entire project on hold.

I only found out about their email when they came down for another meeting on the project. By this time the whole project was delayed by two weeks.

The point about this screed is that the email from PR to me, took only a couple of minutes for them to write, and a couple of milliseconds to arrive at my computer. In other words, speed of message transmission is no guarantee of speed of communication.

We already know that the Imperium, despite its possession of psyker based interstellar comms, suffers desperate delays caused by bureaucracy. We might suppose that the Tau are much more efficient at bureaucracy, and this offsets the slower speed of message transmission.

Surely if it isn't actually defined in a canonical book (or even if it is), then one could just make it up? You can't theorise about something that doesn't actually exist - they're your toy soldiers, and if you want them to communicate in a certain way, then you design their method of communication. As long as it feels 'right' fluff-wise, then who cares if it's at odds with someone else's opinion of it.

If Nurglitch wants to take the statement written in the BFG book as 'fact' then that's his choice - but I don't see why it should affect your ideas of Tau technology. After all, the Tau could use yellow alien spacehoppers with post-tau on them in sealed capsules to get messages between systems. Nothing in any canonical source actually says this doesn't happen, so why not? (Ok, so that was a slightly exaggerated example but the point still stands)

What Killkrazy said is a perfectly good set of parameters for designing that communications system.

As I said before, they're your toy soldiers and you're pretty much free to do whatever the hell you want with their background and fluff. If someone takes an issue to it because it doesn't conform to their ideas or the ideas of Games Workshop, then just tell them to Jog on and get back to painting those space-hoppers.

Dastardly Dave wrote:Surely if it isn't actually defined in a canonical book (or even if it is), then one could just make it up? You can't theorise about something that doesn't actually exist - they're your toy soldiers, and if you want them to communicate in a certain way, then you design their method of communication. As long as it feels 'right' fluff-wise, then who cares if it's at odds with someone else's opinion of it.

If Nurglitch wants to take the statement written in the BFG book as 'fact' then that's his choice - but I don't see why it should affect your ideas of Tau technology. After all, the Tau could use yellow alien spacehoppers with post-tau on them in sealed capsules to get messages between systems. Nothing in any canonical source actually says this doesn't happen, so why not? (Ok, so that was a slightly exaggerated example but the point still stands)

What Killkrazy said is a perfectly good set of parameters for designing that communications system.

As I said before, they're your toy soldiers and you're pretty much free to do whatever the hell you want with their background and fluff. If someone takes an issue to it because it doesn't conform to their ideas or the ideas of Games Workshop, then just tell them to Jog on and get back to painting those space-hoppers.

Cheers

KamikazeCanuck wrote:I'm aware of their "Warp hopping" ship travel. But it's supposed to be 1/5th (i think) as fast as "normal" warptravel.

My apologies, I thought you were asking how the Tau messenger ships could work without having psykers. And yes, Tau drives are slower than Imperial ones "by a factor of five".

Warboss Imbad Ironskull wrote:The instance of a Tau writing a letter can't be applied to the entire Tau Empire. Do you really think an empire as advanced as the Tau would really just send letters back and forth via messenger boats? I doubt it.

Yes. I do. When the only method of FTL travel the Tau have is the warp drives on their starships (and I think it's prudent to mention here that the smallest warp capable ship the Tau have is the "Messenger" class), and conventional real-space methods of communication would take years to get between star systems, I think that an empire as 'advanced' as the Tau would be using starships as couriers.

Warboss Imbad Ironskull wrote:Now yes I'm sure it's used it's even fluff but I doubt it is paper letters sealed in an envelope of some kind and sent off. More likely it is a datta slate or the Tau version of an email.

I never meant to imply that they scratched out letters on parchment or similar. However, the letter, whatever medium it's written on, only gets sent because the "message boat" has "space capacity". Please also note that the text is subtitled "Letters from Pech", so we can discount the idea that the letter is being sent across a literal ocean in a literal boat. Besides, such an 'advanced' race would surely use electronic communication over such small distances.

Warboss Imbad Ironskull wrote:And itt could be that those "messenger ships" are ships designed to carry an advanced relay device for sending messages, it recieves the messages then sends them off to whatever needs them. It could even be a relay station where ships are stationed at intervals throughout the empire and these messenger boats send the message from one ship to another untill it reaches it's destination.

It could be. How, though, are the ships sending these messages to one another across the lightyears of space? And if the ships are physically moving to carry the message many times faster than light could, well, that sounds an awful lot like the pony express system.

Warboss Imbad Ironskull wrote:Even at that there are people who still write letters today it dosen't mean that it's our primary means of communication.

Possible. But what other method of Tau communication do we know about? I can't recall any. So we know that they send can communicate faster than light by transporting them on starships. We know they don't have astropaths, as Tau aren't psykers. We don't know of any alien race described as fulfilling the role of astropath. So in the absence of any other form of communication, 'starship express' seems to be the fastest, and one would assume primary, method of communication the Tau have.

Warboss Imbad Ironskull wrote:The Nicassar squid thing was just how I've always invisioned them so don't take that seriously .

Good to know.

Warboss Imbad Ironskull wrote:But you are wrong, the description of the race is that they are PSYCHIC not telekinetic. Since they are psychic this classifies them as psykers in the 40K universe which is why the Tau have kep their use hidden from the Imperium.

Which description? The one in Battlefleet Gothic states that "Nicassar have powerful minds though and rely on their telekinetic talents [...]". While they are certainly psykers, they're psychic ability is their telekinesis. Their ships are propelled through realspace by "their captains’ psychic powers", i.e., telekinesis. Otherwise they would not take centuries to move from place to place, and would not be carried through the warp by larger Tau vessels.

Warboss Imbad Ironskull wrote:And you're right there isn't any evidence saying that they've been used for interstellar communication but there also hasen't been anything saying that they haven't so arguing it is a mute point. And saying that the Tau woulden't make use of that asset is a poor assumption considering the races knack for using the most usefull traits of their allies.

First off, the term is "moot point", not "mute point". And secondly, where I live a moot point is one that is open to discuss, so that's what I'll continue to do.
We know what role the Nicassar play. They "serve the greater good [...] by providing fleets to scout and explore systems on the fringes of the Tau Emprire". It would make no sense at all to have your communication equipment outside the Empire, since almost all communication would be between systems within the Empire.

Additionally, the assumption that the Tau may not make full use of their asserts is not a poor one. In fact, it's not even an assumption at all. The Tau have been described as "utterly determined that their own methods are the correct methods. As a consequence, they tend to seek out those qualities that best complement their own over those that run counter to them". Hence the savage Kroot are not valued for their skills in close combat, but for the similarities between their talent at stealth and the pathfinders or stealthsuits of the Tau.

Warboss Imbad Ironskull wrote:While it has not been outright stated how the Tau communicate over long distances we can take what fluff we have on the Tau (highly advanced technologically) and their allied races (Nicissar who are psychic and can probably communicate the same way other psykers in 40K do) and come to the conclusion that they either A) Have developed a method of communicating technologically that is fairly fast especially compared to the Imperiums technology or B) they transmit messages via the Nicissar and that they don't simply use "messenger boats".

Your premises are flawed. Technology means nothing when interstellar communication is most available via psychic ability, which the Tau lack. And there is no evidence that Nicassar can communicate over the vast lightyears of interstellar space. And not all psykers are astropaths, nor are all psykers capable of becoming astropaths. So the assertion that Nicassar can "probably" communicate over interstellar distances is bunk. Neither of your conclusions are supported by the fluff, since there is no evidence that they have developed a technological solution and Nicassar have never been mentioned as being able to transmit interstellar messages. Meanwhile, there is direct evidence that the Tau do use message boats.

Warboss Imbad Ironskull wrote:As far as why the Nicissar ships don't have warp space capabilities it could be because as a psychic race they don't use the Warp to travel as a means of avoiding corruption. The Eldar use the webway 1 because it is faster then warp travel and 2 because it is alot safer, the Eldar are an entirely psychic race and so are at a high risk while in the warp. If it applies to them it would apply to the Nicissar as well. Or heck maybe they haden't developed the correct means to do it technologicly. Either way wether their ships use Warp Space to travel or not is irrelevant for if they use it for communication as they are two differant things.

It could be that Nicassar deliberately choose not to use the Warp. But I've seen no evidence for that, and it runs somewhat contrary to the natural curiosity and wanderlust of the Nicassar. There's only so much that can hold your interest in empty space, after all. The webway is a desirable alternative to the warp to all concerned, indeed the Emperor of Mankind was building his own entrance to the Webway before he was struck down. But Nicassar ships do not use the webway, as evidenced by their slow interstellar speeds.
It may be that the Nicassar never developed Warp Drives. But then why have the Tau not equipped Nicassar with warp drives, or employed Nicassar as Navigators? Nicassar ships must be towed through the warp by larger Tau vessels. And they travel through the warp then, which again runs contrary to your assumption that they avoid warp travel due to the risks involved.
And while the ability to travel through the warp and the ability to communicate over long distances using the warp are separate things, as evidenced by the distinction between Astropaths and Navigators, the Nicassar are not described as possessing the talents of an Astropath. They are described as telekinetic. So it's not a case of "we don't know what they do, they could do anything". While we don't know everything about the Nicassar, the omission of a description of any astropathic tendencies in the information we do have is telling by itself.

Nurglitch wrote:More importantly, if you read the Battlefleet Gothic material on Tau FTL flight more closely, you'll find that the psychic weakness of the Tau does not interfere with entering the Warp. Instead it is the gravitic propulsion that fails to penetrate the 'surface' of the Warp, and which forces them to move in short hops.

"Achieving transition to the Warp required more than technology, it required psychically attuned minds and the Tau race boasted no psykers. Without them to guide the transition no amount of power could breach the dimensional barriers". This, to me, clearly indicates that it is the Tau's lack of psychic abilities that prevent them from proper warp travel.
And if you read a little more closely, you'll see that it is by "extending the field generated by the gravitic drive into a wing" that the Tau manage to make hops of decent length. The gravitic drive is an asset, not a hindrance.

Trasvi wrote:^^ On the 'what do the nicassar look like', I believe GW has described them as 'a cross between a polar bear and a pancake'.

Do you have a source for that? I've heard varying descriptions of the Nicassar on a number of websites, but they've all been fabrications by the fans.

Æscholt:

Speaking of close reading, if no amount of power will allow the Tau to penetrate into Warp-space, then the gravitic drive is what fails to penetrate into Warp-space, instead forcing short hops. Clearly the drive both fails to enable full Warp immersion, and enables FTL travel.

Perhaps if you consider it this way, via the logic of necessary and sufficient means. The Warp-drive is necessary to become immersed in the Warp, but not sufficient. Likewise having a Navigator is necessary, but not sufficient. The Tau have neither Warp-drive nor Navigators, so they cannot make the transition to Warp-space or navigate that space once they have done so. The Gravitic-drive does not immerse them in Warp-space, and so the presence of a Navigator makes no difference to the duration of travel. Instead it is the Gravitic-drive that both allows travel and restricts it to short hops.

Something to consider is that Warp-drive is sufficient to transition a ship into Warp-space because the background is riddled with transitions to Warp without a Navigator (most notably "The Flight of the Eisenstein". It's just suicide to do so. If we are to square that with the comment that no amount of power will enable one to breach the dimensional barriers, it follows that psykers are employed somehow in the manufacture of a Warp-drive so that its power is directed in the right fashion so as to breach the great divide.

The correct inference, then, is that the problem may be the weak psychic nature of the Tau, but only in the sense that they lack the sufficient psychic talent to both manufacture Warp-drives and breed Navigators. A Navigator isn't sufficient to turn a Gravitic-drive into a Warp-drive.

@ Nurglitch:
The Tau have warp drives, in addition to their gravitic drives. They developed the gravitic drives to move around their own system, and then found and duplicated an alien warp drive. This is in the BFG background for Tau, I'm not sure quite how you missed it. It follows that the warp drive is what allows the Tau to make their "partial transitions" into the warp, and although the gravitic drive is essential in keeping the Tau within the void between warp and realspace for longer, it is not what puts them there.

Regarding the necessity of Navigators, the lack of psykers certainly prevents Tau from entering the warp. As I mentioned, "psychically attuned minds" are described as a requirement. It may be in the case of the Eisenstein (which I'm not intimately familiar with, it's been a while since I read the book) that the natural psychic abilities of the crew were sufficient to breach the 'dimensional barriers'. Remember, normal humans are around rho or pi on the scale used in 40K (which corresponds neatly with the Greek alphabet, alpha being high), and the Tau sit somewhere below them, between psi and sigma. I would personally think it fitting if the Tau average two steps below humans, that is, at about the tau level.