Good luck with trying to make a studio-only setting that hangs together. It sounds fun, but I suspect it isn't quite possible to do. It's not just the freelance fluff-writers who contradict studio fluff.
Quite so, quite so - though I do find the studio fluff much more consistent than the many individual interpretations published in the licensed material. Probably just because it's one big studio whose staff did not change much over a long time ... and because GW is very fond of copypasting texts from older products.
The more people you have working on a setting, the more likely it is that they bring ideas into it that conflict with something that somebody else wrote. And since GW seems to prefer the muddled "it's all possible" approach rather than Battletech's or Star Wars' clear canon policy, it is all equally valid, and we end up having to cherrypick.
Doesn't it say some were that astartes don't stop growing and that 7 feet is just a starting height?
Never heard of such a thing - though I wouldn't discount the possibility that some author may have published something like that!
Personally, I'd find that highly impractical. Growing out of your armour all the time?
GorkaMorka, that's where you'll find "Ork stuff works because Orks think it will work" references.
Come to think of it, that is one book I've never had the chance to look at!
It said some veteran first company terminators ARE 12 FEET TALL!!!!