Well i posted this before the crash but...
As i said, Memnoch, i tried searching this info with "search" but it said something about a script error so...

Ok, my question is quite simple: do 2 handed weapon style bonuses apply when wielding a bow (or xbow) ?? So, is it worth to put 2 handed weapon style profs to an archer ??

PS: damn crashes !!!

Don't you get a reaction adjustment with more proficiencies regarding a weapon or style? My guess is that this would show up on your character's profile. Hope this helps I've never checked it myself.