Reading through the codex as I type.
Ward's still a complete hack as a fluff writer. His new iteration of "doom/nemesis/psy" everything wouldn't have passed muster at a 10th grade creative writing class. I don't know why the editors at GW give him a pass.
It's ridiculous DC comics-esque writing, and completely out of tune with the rest of the game. It's just as bad, if not more so, than the tragedy that is the naming conventions in the BA 'dex.
And yes, given all the fluff surrounding the GK, particularly that their gene seed is directly from the Emperor, I find it very hard to believe any need for them to annoint themselves in the blood of Sisters, who've already proven to resist the aforementioned taint, just to be able to perservere. I would've thought it even slightly misogynistic, save that Ward spares the rod nowhere else, either.
Though the bit where a bunch of GK, having successfully defeated the Company of Shadow (oooh, boo-scary!) promptly get fusion-bombed out of existence (save for Modrak) by Huron Blackheart, who wasn't even aware they were there. He was hoping to settle his own score with the CoS...amusing.
Now, as a quick aside--I am very put out that inquisitors are an HQ only option...*razzlefrazzleglurbargh*
Edit: This point is only further supported a few codex paragraphs later when the GK's attack Huron's flagship, only to be assisted by the ghosts of their fusion-bombed brethren?!?!?! Utter. Fail.