Do the effects of Two-Weapon Fighting and Double Slice stack with the effects of the Draconic Style and Draconic Ferocity feats?
I would assume so especially in the new light that the monk is supposed to be doing nothing more than TWF when flurrying (with a built in double slice) i would hope that they do.
I think it would be interesting and certainly give greater credance for playing a strength based monk. Under this double slice would allow for full strenth to both attacks. Draconic style adds 1.5 strength bonus to the first attack while keeping full strength to off hand attacks. Finally, adding in the bonus from braconic ferocity would mean double strength modifier to the first attack and 1.5 strength modifier to the off hand attack.
I have a feeling that this is not what they wanted as the Draconic Style feats feel like they were meant to emulate double slice. However, it would be awesome if they did stack.
Not quite sure what you're asking...
Dragon Style's increase in Str to damage only works on unarmed strikes.
Assuming you're not a monk, and therefore need to take Double Slice to up your offhand attack damage... I'd say yes, it all stacks.
Your first UAS is made at 1.5xStr + .5x Str(from Ferocity)
Any other primary hand damage will be made at 1x Str + .5x Str(Ferocity)
Offhand damage will be made at 1x Str(DSlice) +.5x Str (Ferocity)
Just wondering how they would work together for a monk build or an unarmed fighter build I was debating on playing. Basically, as I said in my above post, wondering since bouble slice puts you at strength modifier for both unarmed attacks. The draconic style puts you at 1.5 for first attack and full strength damage for the off hand attack. Then draconic ferocity further stacking for double strngth for first attack and 1.5 damage for the off hand attack.
Wanted to see if others concured with my line of logic.