As other have pointed out the fluff is all over the place. Generally speaking a
40k battle is a small and probably fairly insignificant battle in a grander scheme of things. Whilst it makes no sense that a platoon, some 50 guardmsen, represent the entire regiment breaking the oposing army it does make sense for a platoon to hold a a few buildings, to secure a small piece of a road, to grab a box of something important and then retreat, to escort civilians out of a city and so on. A
40k game is a small scale engagment. If you view it from that perspective the guard makes the most sense out of most forces since their very versatile in what they're expected to do in a war.
Also since it hasn't been said already I'd like to point at the old Epic
40k game as the most fluffy
40k game to date.
I'd say the guard are fairly representative of their fluff. The same goes for orcs and tyranids. I'd say less so about eldar, deamons and tau. Astartes, necrons and knights are pretty much not representative of their fluff whatsover.
YeOldSaltPotato wrote:
That said, I was wondering the other day if having an side board would benefit
40k. Effectively have a 'these guys are way behind the lines' and a variety of ways to move from the field to the side board that makes those recon troops actually do something useful other than board denial, have flyers do something other than holding patterns across the board, that kind of thing.
EDIT: I've been thinking about similar things, with far away artillery contributing to a fight and ships bombarding from space, that sort of thing.
EDIT 2: As to the discussion of the competence of a space marines I find the deathwatch
RPG by Fantasy Flight Games to be the best guidline, at least to their individual and group based capabilities.