Originally Posted by
jazztromboneguy
#1 and #3 do not stack as they are both compentency bonuses. 1 overrides 3 as the bigger bonus
Black Dragonhide (or the docent of quickening or the quiver of alacrity) stacks with 1 or 3 but not both
The armor, docent, and quiver I would assume would not stack with eacher other, as they are all from equipement. Generally equipment bonuses do not stack with each other.
Also, remember that Haste will stack with 1 or 3 but may not with 2 (or the equivilents), although due to my own testing, I think they do (probably is a bug)