Doable or not? It's either that or a 6/6/8 split with rogue and artificer using repeaters for the past life, but I would like to play a "proper" THFing barbarian once. I just can't stand how two-handed fighting looks in general, it's like staggering around drunkenly. Only the q-staff looks good.
My tentative plan for a q-staff user is 15 barb/3 rogue/2 fighter OR 15 barb/4 rogue/1 fighter. Ravager's Blood Strength will probably be more useful than Staff Specialization from the TA tree, though the increased crit multiplier and threat range would be nice to have. The question is how deep I need to go into the TA tree.
Tier 4 gives access to No Mercy, 30% extra damage to helpless opponents, but loses me a feat from fighter level 2. If No Mercy stacks with Bully from Ravager and Sense Weakness from FotW it would probably be worth it, if they don't stack I believe the extra feat will be better, has someone tested if they stack or not?
Furthermore, with the high attack speed of q-staves and the doublestrike bonus from Quick Strike, how useful are the cleaving feats? I must admit I haven't really followed the development on that front, I recall that cleave and great cleave used to not cause extra attacks from doublestrike, is that still the case?
Does doublestrike cause extra glancing blows on normal attacks? It probably should, but in this game it's sometimes hard to tell.