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 Formosa wrote:
"send a battle brother to take a town, send a squad to take a city, a chapter to take a world, send a legion to destroy a culture, there are of course exceptions to this general rule, the enigmatic eldar and the hordes of the ork"
Roboute guilliman, know no fear.

Yes a company can fight and win against a whole planet, you all seem to miss the obvious, when facing such overwhelming numbers you hit and run, they have even made a bit of fluff that describes how a single unsupported company took a world.
Paraphrased from memory
phase 1 orbital bombardment, targeting infrastructure such as power, water and waste plants.
Phase 2 orbital drop on orbital defence locations, disable, capture or.destroy.
Phase 3 target command echelons of enemy forces and ambush and capture/destroy, rinse ans repeat.
Phase 4 hit and run warfare, guerilla warfare, target ammo, food and water supplies, marines need these in lesser amounts
Phase 5, target large formations of enemies with orbital attacks that threaten to cut off allied forces
phase 6 as enemy uses smaller formations to avoid orbital attacks, use superior movement and skill to surround and destroy these formations.
Phase 6 repeat Phase 4/5/6
Phase 7 increasingly desperate enemy is both in need of food and water supplies and ammo resources are thin, leadership is either incapacitated or in no shape to fight, engage large scale assault on any remaining strongholds
Phase 8 enemy surrenders.

At no point in this assault are the space marines in a straight battle with there enemy,

This generally makes sense, but there are some problems:
- It makes a lot of assumptions about the capability of the marines against the given enemy. The approach seems acceptable for conventional foes, but there are plenty of dire situations(the one marines might more often be called in for in the first place) where some of this won't work.
- There are instances of chapters using much less careful/logical approaches, so I think we have two competing images of the Astartes: the surgical strike specialists called in for small but important manuevers no other Imperial force can pull of vs. the stalwart defenders of humanity, massed shoulder-to-shoulder, charging the enemy ranks to obliterate them in close assault or standing their ground against all odds against hordes of monstrosities and heretics.

...and certainly 10,000(or greater) as a standard chapter size wouldn't *harm* their ability to fight in the manner you've described.

Why didn't they stick with 4000 marines per chapter?

 Themanwiththeplan wrote:
Why didn't they stick with 4000 marines per chapter?

When was this the accepted number? I thought it was always 1000.

 Vaerros wrote:

 Formosa wrote:
"send a battle brother to take a town, send a squad to take a city, a chapter to take a world, send a legion to destroy a culture, there are of course exceptions to this general rule, the enigmatic eldar and the hordes of the ork"
Roboute guilliman, know no fear.

Yes a company can fight and win against a whole planet, you all seem to miss the obvious, when facing such overwhelming numbers you hit and run, they have even made a bit of fluff that describes how a single unsupported company took a world.
Paraphrased from memory
phase 1 orbital bombardment, targeting infrastructure such as power, water and waste plants.
Phase 2 orbital drop on orbital defence locations, disable, capture or.destroy.
Phase 3 target command echelons of enemy forces and ambush and capture/destroy, rinse ans repeat.
Phase 4 hit and run warfare, guerilla warfare, target ammo, food and water supplies, marines need these in lesser amounts
Phase 5, target large formations of enemies with orbital attacks that threaten to cut off allied forces
phase 6 as enemy uses smaller formations to avoid orbital attacks, use superior movement and skill to surround and destroy these formations.
Phase 6 repeat Phase 4/5/6
Phase 7 increasingly desperate enemy is both in need of food and water supplies and ammo resources are thin, leadership is either incapacitated or in no shape to fight, engage large scale assault on any remaining strongholds
Phase 8 enemy surrenders.

At no point in this assault are the space marines in a straight battle with there enemy,

This generally makes sense, but there are some problems:
- It makes a lot of assumptions about the capability of the marines against the given enemy. The approach seems acceptable for conventional foes, but there are plenty of dire situations(the one marines might more often be called in for in the first place) where some of this won't work.
- There are instances of chapters using much less careful/logical approaches, so I think we have two competing images of the Astartes: the surgical strike specialists called in for small but important manuevers no other Imperial force can pull of vs. the stalwart defenders of humanity, massed shoulder-to-shoulder, charging the enemy ranks to obliterate them in close assault or standing their ground against all odds against hordes of monstrosities and heretics.

...and certainly 10,000(or greater) as a standard chapter size wouldn't *harm* their ability to fight in the manner you've described.

I totally agree with what your saying there, but with a few caveats.

1: as guilliman said himself, this does not always apply, it is a general truth, and astartes are primarily used against conventional human forces.
2: certain chapters would not do this I agree, could you see the flesh tearers or black Templars doing this haha, dark angels and ultras absolutely would though.
3: legions...10k marines...who needs guile with a beat.stick that big!

Because GW doesn't understand scale. 1,000 Space Marines, given their presented capabilities, would not be able to conquer the United States. Nevermind a whole planet. Nevermind multiple planets.

Because that's a minimum-strength legion, that's why.

 Harriticus wrote:
Because GW doesn't understand scale. 1,000 Space Marines, given their presented capabilities, would not be able to conquer the United States. Nevermind a whole planet. Nevermind multiple planets.

Yes they would, quite easily infact, I will go by my previous post

Phase 1, locate major cities power and main infrastructure, orbital strike and disable, target main food manufacturing areas, destroy.
During step 1 send in strike team of 10 marines to white house via pod, destroy president and any forces on location, do the same to the Senate, withdraw via thundeehawk. Orbital strike Pentagon.
Step 2, us in disarray due to military command being destroyed within hours, strike massing us military forces, us will now not mass in large groups.
Step 3, orbital drop onto key US battlegroups, isolate and destroy airbases and tank formations
Step 4, rinse and repeat step 2/3, us morale drops due to mass starvation, us military morale drops due to large casualties, start large scale propaganda campaign demanding surrender.
Step 5, wipe out large cities to force us military to surrender or face mounting casualties.
Step 6, victory

What almost all of you seem to fail to understand is that marines will not hold.positions, they will get in, cause massive casualties and leave before a decent counter attack could occur, they are 100% safe in orbit, a chapter would easily annihilate earths defences piecemeal.

But 1000 is a tiny number. No matter how tough you are as a space marine if there are enough numbers will triumph. The marines are hiding in the forest? Then carpet bomb the crap out of it. Ten dead marines is one percent of the chapter. You send one million men to combat 1000 marines they are outnumbered 1000 to one. And even against crazed cultist, let alone an organised fighting force that is something NO marine could survive


Automatically Appended Next Post:
And let's face it, 1,000,000 men is how big a mid-sized country's army is, let alone a planet in wartime.

thetallestgiraffe wrote:But 1000 is a tiny number. No matter how tough you are as a space marine if there are enough numbers will triumph. The marines are hiding in the forest? Then carpet bomb the crap out of it. Ten dead marines is one percent of the chapter. You send one million men to combat 1000 marines they are outnumbered 1000 to one. And even against crazed cultist, let alone an organised fighting force that is something NO marine could survive

Well, duh. Isn't that pretty much how the Imperium wants it?

The Space Marines are not supposed to roflpwn everyone on their own. If you want the hammer, you get the Imperial Guard. The Adeptus Astartes post-Heresy is not meant to conquer entire star systems on their own anymore, it's meant to support the ones that do. Because ultimately, those Chapters are not fighting for their own glory and gain (or rather they are not supposed to), but for the teeming masses of mankind. Codex Astartes Space Marines are "designed" to add their strength to the Imperial Guard, and the weaknesses you mentioned would be taken care of by the Guard and the Navy providing the necessary screening. When a Chapter goes rogue, on the other hand, those weaknesses are exactly what the IoM hopes to exploit in order to get rid of the traitors. Exactly like how it works with the separation of capabilities between individual IG regiments, or the Guard and the Navy as a whole.

"Divided we stand."

 1hadhq wrote:

- one click bundles of a chapter of 1200 marines cost 12.000$. Maybe charging 100.000$ didn't seem viable??

This bit quoted so the non-euros don't get confused. Periods and commas get used in different ways by different parts of the world.

For most of us, writing a number like 12.000 is no different to writing 12 (but you are putting down 5 significant figures). If it's TWELVE THOUSAND We would write the number either as 12 000 or 12,000.

Numbers written like the latter, however, tend to confuse euros in the same way - as the comma tends to be used as a decimal marker there. They see 12,000 as we see 12.000.


Oh how I wish the one-click bundle was only $12 (it's 17 THOUSAND here).

thetallestgiraffe wrote:
But 1000 is a tiny number. No matter how tough you are as a space marine if there are enough numbers will triumph. The marines are hiding in the forest? Then carpet bomb the crap out of it. Ten dead marines is one percent of the chapter. You send one million men to combat 1000 marines they are outnumbered 1000 to one. And even against crazed cultist, let alone an organised fighting force that is something NO marine could survive


Automatically Appended Next Post:
And let's face it, 1,000,000 men is how big a mid-sized country's army is, let alone a planet in wartime.

Yep that's true, but what are they going to carpet bomb, space marines can get in and cripple an enemy before any meaningful defence can be brought to bare, plus as already stated, those b52 bases have already been orbital striked.

Drop pod in, kill, thundeehawk out, marines have shown in fluff they can do this and leave a mission area within minutes, we literally have no defence against this, conventional warfare is useless against astartes, this is the whole point of there creation

I agree, it's not only a matter of scaling chapters up, but of scaling up imperial defenses against one chapter. You could maybe make 20 times more marines, but you can't raise the strength of everything else by the same amount.

In some legions in HH the company strength is stated as 4,000 marines made up of 4 formations/units with 4 line Captains under the Chapter Master. So why did they reduce a chapter size to just 1,000?

 Themanwiththeplan wrote:
In some legions in HH the company strength is stated as 4,000 marines made up of 4 formations/units with 4 line Captains under the Chapter Master. So why did they reduce a chapter size to just 1,000?

During the Great Crusade the legions were allowed to organize themselves as they saw fit, so that number will have only held true for a few of, or maybe even just one of the legions. Blood Angels for instance only had one chapter master, Raldoron, and numbered 120,000.

Too much power in the hands of a single marine. Marines quite simply cannot be trusted with that amount of power.

They have proven themselves unworthy of it.

Hilariously if I recall correctly, most of the legions that turned to Chaos were following the sacred numbers of Chaos before they actually turned. Mortarion's elite guard never strayed more than 49 paces from him (49 Is 7 times 7. 7 is Nurgle's sacred number). Horus's theming around the number 4 could represent the 4 chaos gods (er, if that whole 4 thing was for the Luna Wolves). Etc etc.

Perhaps Roboute chose 1,000 in part because the numbers don't match up to any chaotic occult ritual.

 Orblivion wrote:

 Themanwiththeplan wrote:
In some legions in HH the company strength is stated as 4,000 marines made up of 4 formations/units with 4 line Captains under the Chapter Master. So why did they reduce a chapter size to just 1,000?

During the Great Crusade the legions were allowed to organize themselves as they saw fit, so that number will have only held true for a few of, or maybe even just one of the legions. Blood Angels for instance only had one chapter master, Raldoron, and numbered 120,000.

Not quite correct, in "Fear to Tread", Raldoron's title is "First Captain", afaik there is no "Chapter Master" or chapters at that time. It seems to me that the idea came from the UM (little wonder), they had chapters before the heresy.

 Formosa wrote:

 Harriticus wrote:
Because GW doesn't understand scale. 1,000 Space Marines, given their presented capabilities, would not be able to conquer the United States. Nevermind a whole planet. Nevermind multiple planets.

Yes they would, quite easily infact, I will go by my previous post

Phase 1, locate major cities power and main infrastructure, orbital strike and disable, target main food manufacturing areas, destroy.
During step 1 send in strike team of 10 marines to white house via pod, destroy president and any forces on location, do the same to the Senate, withdraw via thundeehawk. Orbital strike Pentagon.
Step 2, us in disarray due to military command being destroyed within hours, strike massing us military forces, us will now not mass in large groups.
Step 3, orbital drop onto key US battlegroups, isolate and destroy airbases and tank formations
Step 4, rinse and repeat step 2/3, us morale drops due to mass starvation, us military morale drops due to large casualties, start large scale propaganda campaign demanding surrender.
Step 5, wipe out large cities to force us military to surrender or face mounting casualties.
Step 6, victory

What almost all of you seem to fail to understand is that marines will not hold.positions, they will get in, cause massive casualties and leave before a decent counter attack could occur, they are 100% safe in orbit, a chapter would easily annihilate earths defences piecemeal.

Step 3 is where you run into problems, as the US can mobilize more military formations than there are individual Space Marines.

Also doubtful 10 Space Marines could take out the White House-Senate area. Once the fighter jets or attack helo's show up they're pretty screwed.

 Harriticus wrote:

 Formosa wrote:

 Harriticus wrote:
Because GW doesn't understand scale. 1,000 Space Marines, given their presented capabilities, would not be able to conquer the United States. Nevermind a whole planet. Nevermind multiple planets.

Yes they would, quite easily infact, I will go by my previous post

Phase 1, locate major cities power and main infrastructure, orbital strike and disable, target main food manufacturing areas, destroy.
During step 1 send in strike team of 10 marines to white house via pod, destroy president and any forces on location, do the same to the Senate, withdraw via thundeehawk. Orbital strike Pentagon.
Step 2, us in disarray due to military command being destroyed within hours, strike massing us military forces, us will now not mass in large groups.
Step 3, orbital drop onto key US battlegroups, isolate and destroy airbases and tank formations
Step 4, rinse and repeat step 2/3, us morale drops due to mass starvation, us military morale drops due to large casualties, start large scale propaganda campaign demanding surrender.
Step 5, wipe out large cities to force us military to surrender or face mounting casualties.
Step 6, victory

What almost all of you seem to fail to understand is that marines will not hold.positions, they will get in, cause massive casualties and leave before a decent counter attack could occur, they are 100% safe in orbit, a chapter would easily annihilate earths defences piecemeal.

Step 3 is where you run into problems, as the US can mobilize more military formations than there are individual Space Marines.

Also doubtful 10 Space Marines could take out the White House-Senate area. Once the fighter jets or attack helo's show up they're pretty screwed.

If the space marines could actually drop in and kill any fething person in the OO in mere minutes, they are pretty safe from any fighter jet the current US military has, from what I know. Preparing a jet and having it take off, under emergency conditions, still takes something like 15 minutes. Maybe they could cut it to 10 if they really risked a lot (which, in this cased, sounds like the thing to do). Maybe I can find the source for that.
Edit1: orthography

KhornedBeef wrote:

 Orblivion wrote:

 Themanwiththeplan wrote:
In some legions in HH the company strength is stated as 4,000 marines made up of 4 formations/units with 4 line Captains under the Chapter Master. So why did they reduce a chapter size to just 1,000?

During the Great Crusade the legions were allowed to organize themselves as they saw fit, so that number will have only held true for a few of, or maybe even just one of the legions. Blood Angels for instance only had one chapter master, Raldoron, and numbered 120,000.

Not quite correct, in "Fear to Tread", Raldoron's title is "First Captain", afaik there is no "Chapter Master" or chapters at that time. It seems to me that the idea came from the UM (little wonder), they had chapters before the heresy.

Fear to Tread, pg. 33: "Raldoron was equerry to the primarch, and held the new honorific 'Chapter Master', serving in a similar role to the warriors of Horus's advisory cadre, the Mournival." We also see him called chapter master in Horus Rising.

 Orblivion wrote:

KhornedBeef wrote:

 Orblivion wrote:

 Themanwiththeplan wrote:
In some legions in HH the company strength is stated as 4,000 marines made up of 4 formations/units with 4 line Captains under the Chapter Master. So why did they reduce a chapter size to just 1,000?

During the Great Crusade the legions were allowed to organize themselves as they saw fit, so that number will have only held true for a few of, or maybe even just one of the legions. Blood Angels for instance only had one chapter master, Raldoron, and numbered 120,000.

Not quite correct, in "Fear to Tread", Raldoron's title is "First Captain", afaik there is no "Chapter Master" or chapters at that time. It seems to me that the idea came from the UM (little wonder), they had chapters before the heresy.

Fear to Tread, pg. 33: "Raldoron was equerry to the primarch, and held the new honorific 'Chapter Master', serving in a similar role to the warriors of Horus's advisory cadre, the Mournival." We also see him called chapter master in Horus Rising.

I recognize my failing and will be sure to correct it.
Thank you


Automatically Appended Next Post:
Hope I didn't make the same mistake with the BA legion structure

Step 3 is where you run into problems, as the US can mobilize more military formations than there are individual Space Marines.

Also doubtful 10 Space Marines could take out the White House-Senate area. Once the fighter jets or attack helo's show up they're pretty screwed.

What are the helos and fighter-jets going to do, rocket the Senate building? You have Space Marines in there who are just wading through dozens of Secret Service Agents like they were gnats, killing Senators, aides, lobbyists and anyone else in the area left, right and fething center with armor-piercing, mass-reactive explosive bullets.

It's one thing for people to see others get wounded in combat... quite another to see a dude covered in the best armor your military can provide literally *explode* in front of you from a single round from a pistol, meanwhile your assault rifle hasn't even chipped the paint on these behemoths, and they've racked up a body-count of 200+ people in four minutes using melee weapons and small-arms.

 Psienesis wrote:

Step 3 is where you run into problems, as the US can mobilize more military formations than there are individual Space Marines.

Also doubtful 10 Space Marines could take out the White House-Senate area. Once the fighter jets or attack helo's show up they're pretty screwed.

What are the helos and fighter-jets going to do, rocket the Senate building? You have Space Marines in there who are just wading through dozens of Secret Service Agents like they were gnats, killing Senators, aides, lobbyists and anyone else in the area left, right and fething center with armor-piercing, mass-reactive explosive bullets.

It's one thing for people to see others get wounded in combat... quite another to see a dude covered in the best armor your military can provide literally *explode* in front of you from a single round from a pistol, meanwhile your assault rifle hasn't even chipped the paint on these behemoths, and they've racked up a body-count of 200+ people in four minutes using melee weapons and small-arms.

This combined with the destruction of the Pentagon from orbit, and raid on white house, the Us simply has nothing that can compete, imagine how damaged morale would be when a marine punches an Abrams to death or brings down an apach
With his "small arms"

Very little about Space Marines makes sense once you start drilling into it, the Space Marines just do not work and would be functionally irrelevant in any realistic take on the 40k universe, they are simply too few lacking too many capabilities and operating over too large an area and take far too many resources to support, and be so small as to equate to a few hours worth of IG recruit in their total military value. They also are portrayed in a wildly inconsistent manner, as everything from basically big guardsmen, to divine demi-gods, and everything in between, and as doing everything from engaging in frontal assaults and trench warfare to stealth assassinations and shock assault and massive armored tank warfare and everything in between, which realistically 90% of which a military formation like a Space Marine chapter is completely unsuited to. To say nothing of logistical issues where we have SM chapters that only recruit once every ten/13/etc years but are constantly engaged in warfare and would extirpate themselves likely before they ever got to their next recruitment cycle.

This is why 40k is a really a Fantasy universe, not so much a "Science Fiction" one, it's just set in space instead of castles and dungeons.

Oh I dunno, I think they do work - in principle. The basic idea is sound: elite shock troops to turn the tide where your regulars run into trouble. They don't have to be many, just enough to tip the scales. The Storm Trooper regiment works by the same concept, just on an even smaller scale (compensated for by greater linkage/integration with the forces on-site).

The only real issue I could see is that a lot of writers (not to mention fans) do not use them in this manner but rather present them as line troops fighting most of their battles alone. It's a break between the general descriptions of their tasks, and the retelling of individual incidents. It does, however, help a lot to consider the various game designers' and novel authors' statements regarding "historical accounts" being distorted by legend, myth, and propaganda. Even the 6E Rulebook has a disclaimer pointing out how unreliably these stories are.

 Lynata wrote:
Oh I dunno, I think they do work - in principle. The basic idea is sound: elite shock troops to turn the tide where your regulars run into trouble. They don't have to be many, just enough to tip the scales. The Storm Trooper regiment works by the same concept, just on an even smaller scale (compensated for by greater linkage/integration with the forces on-site).

Right, but the problem is that, even then, they're would still be so rare/so few, and so widespread that they'd be absent in the vast majority of such situations, and/or take such casualties that they'd quickly be wiped out in an Imperium engaged in brutal warfare almost everywhere for 10,000 years without pause across 10,000,000,000,000 (ten trillion) cubic Light Years of space.

The only real issue I could see is that a lot of writers (not to mention fans) do not use them in this manner but rather present them as line troops fighting most of their battles alone.

This is also a huge deal and very true.

It's a break between the general descriptions of their tasks, and the retelling of individual incidents. It does, however, help a lot to consider the various game designers' and novel authors' statements regarding "historical accounts" being distorted by legend, myth, and propaganda. Even the 6E Rulebook has a disclaimer pointing out how unreliably these stories are.

This is true, but even then, there's just so much of the stuff that the more "accurate" type fluff is often the exception.

Vaktathi wrote:Right, but the problem is that, even then, they're would still be so rare/so few, and so widespread that they'd be absent in the vast majority of such situations, and/or take such casualties that they'd quickly be wiped out in an Imperium engaged in brutal warfare almost everywhere for 10,000 years without pause across 10,000,000,000,000 (ten trillion) cubic Light Years of space.

Oh, I don't think so - they just wouldn't show up a lot. The way I interpret the setting, the Marines carefully pick their battles based on their own capacities at that point in time as well as the importance of the battle, then send one or more Battle Companies (backed by the Reserves), and after that, should it truly be necessary, scale back their activities a bit for a decade or so to recruit new troops in order to fill up their ranks again. 40k's timeline is so huge, it doesn't matter if a Chapter has a hundred or a thousand famous battles logged somewhere. There was sufficient time for them to fight those, and still you can have years between individual combat actions (which you may need sometimes, given the peculiarities of Warp travel).

tl;dr: maybe Space Marines just aren't as common in the various battles throughout Imperial space (and beyond) as the material sometimes lets them appear to be. 10.000 years and a million worlds - I hereby claim that what we know isn't even a single percent of the battles fought by Imperial forces. It is just the tiny bit that is most famous and legendary. Codex fluff makes it very clear that it's the IG that does the most fighting, whilst it describes the Space Marines as pretty much being the Imperium's fast-response fire fighters, and in this light, I believe everything makes sense.

I understand this is a much more grounded and less fantastical interpretation of the material, but this way I can make it work in my mind, and it isn't contradicted by the source material - so that's what I'm personally running with. I guess I just prefer "my" settings to conform to a certain degree of "fantastical realism" in order to be more immersive.

Vaktathi wrote:This is true, but even then, there's just so much of the stuff that the more "accurate" type fluff is often the exception.

Oh yes - but "unfortunately" this is to be expected, given the format this information is presented to us. If you consider the aforementioned official statements, it is almost certain that most of the incidents we know about are quite intentionally the exception of the rule, listed only because they were so much more epic and heroic than the norm. Often enough, real life history has been no different. If you want to see the other side of the coin, there's often a good chance you find something in the Codex of an army's enemy, though.
Just because C:SM doesn't contain any bit of fluff about the Celestial Lions being wiped out on Armageddon doesn't mean it didn't happen. Just because C:SM doesn't contain any bit of fluff about multiple Chapters of Astartes having been purged by the Adepta Sororitas doesn't mean it didn't happen. etc.

 Lynata wrote:
Oh yes - but "unfortunately" this is to be expected, given the format this information is presented to us. If you consider the aforementioned official statements, it is almost certain that most of the incidents we know about are quite intentionally the exception of the rule, listed only because they were so much more epic and heroic than the norm. Often enough, real life history has been no different. If you want to see the other side of the coin, there's often a good chance you find something in the Codex of an army's enemy, though.
Just because C:SM doesn't contain any bit of fluff about the Celestial Lions being wiped out on Armageddon doesn't mean it didn't happen. Just because C:SM doesn't contain any bit of fluff about multiple Chapters of Astartes having been purged by the Adepta Sororitas doesn't mean it didn't happen. etc.

This seems counter to your point. It implies that their are far more casualties of space marines over time since most events go unreported. I agree with the OP that 100,000 marines seem far too small a number to have any real impact on the setting, mainly because the setting described is so vast.

Believe me, I'm all about the capabilities of an elite vanguard of super soldiers making decisive strikes on a battlefield, but the attrition rate during even a modest campaign would probably cripple a chapter for decades. The value of such a small contingent actually decreases in worth because in so deploying such a super elite force a commander would be wiser to pull them from any serious combat lest they are destroyed.

Maybe my view is skewed by the game itself. Play a large game of 3000 points against orks and even an overwhelming victory will cause dozens of space marine casualties. Losing 2% of what is supposed to be an entire chapter in a skirmish doesn't bode well for the survival of an organization that is positively glacial in replacing its losses.

Oh, I didn't say that. It may well be that casualty-heavy missions are just as "rare" as those legendary fights we get to read about. Space Marines are still incredibly tough, and even if they are punched out in battle (which isn't all that hard to do, going purely by GW's Inquisitor RPG) they may well survive their injuries and recover. There's something in-between combat-capable and casualty, and this applies to losses in the TT as well.

Thing is, if Space Marines are used "correctly", that is according to their general description and in situations where they get to play all their cards right, you'll have an elite shock unit blasting through an enemy who is utterly unprepared to face anything like them (and I actually see the standard 40k TT battle as a "things gone wrong" kind of deal, since both sides have an equal points value - something that shouldn't happen for the Astartes).
This would then likely result in few casualties. It would, however, also not be as "special" since it wasn't such a legendary fight as it was obvious from the start that the enemy wouldn't have a chance. Who wants to read about a clearly superior force effortlessly eradicating a disadvantaged foe? That's just not epic enough.

... but it would make the Space Marines work, in terms of realism.

The Fall of Medusa PDF from GW's global campaign includes a reference to the Iron Hands Chapter exterminating the indigenious life on a planet to prepare it for colonisation. Does anyone think this was a challenge? Surely not - it was butcher's work. And so no further stories about this incident are available. Genocide as a footnote in history, because the population did not offer resistance.

 Lynata wrote:
Oh yes - but "unfortunately" this is to be expected, given the format this information is presented to us.

Of course, except for some BRB entries copy and pasted from prior editions and the Index Astartes articles, the majority of the information we get is not presented that way at all. Very frequently we're a fly on the wall, or inside the character's head. We just get the potato head "build your own unique canon out of this pile of crap" approach, because it's easier for GW than competence.

I mean, we're supposed to assume that all Marines have a Nixonian compulsion to record everything they say and do, complete with detailed descriptions of settings and moods and the thoughts and emotions of others, and even though they are frequently torn apart in the warp, eaten and turned to poo by gribblies, or utterly annihilated by whatever megaweapon, these records somehow survive and are recovered by people who further mystify and embellish them even though they would be classified or destroyed per usual Imperial MO.