(batting lightning bolts around like a cat witha bouncy ball of yarn) zZz<(^-^)>zZz
And btw: unfortunatly it has come to my discovery that yes, the shaman style of play is HEAVILY based on gear. So much so that it takes hours of for-thought to figure out what weapons you should be getting.
With that aside. Assuming you have top end gear, and you main hand is 2.6 speed and your offhand is 1.5 speed, for raid siutations it makes more sence to have rock biter on your off-hand because it generates less threat while maintaing the damage of windfurry if not more than windfurry(not considering if your attack speed decreases further yet due to heroism or a meta gem, in which case the damage of windfurry cannot be denyd. However once again rockbiter will genereate much less threat while still comming close to windfurry's dps).
Of course non of this realy matters as you have chosen the leafy side of the force -_-