Originally Posted by
Fornaw
There was a really old EJ thread where someone posted this, I think it was determined in the end that he was confused and the AP bonus of windfury was not receiving the offhand penalty, but this was so long ago it may have changed.
Thing is the AP bonus of windfury is pretty small compared to the damage of the attack itself. Even using a 2.8 speed weapon and using the level 80 version of the attack (+1250 AP) the difference between OH takes the damage penalty on the AP boost component and OH does not take the damage penalty on the AP boost component is 360 damage total (both additional attacks and with all the talents that should effect it).
Something that doesn't go in the Enh FAQ is that, while soloing, you are rarely going to get to 2x windfury a mob anyway, which means an OH windfury isn't going to "steal" a proc from the mainhand. It might be interesting to program Enh sim for these sort of very short fights just to see what it makes of them.