Ok for a combat dagger rogue, which most PvE raiding rogues are or should be,  only your special attacks really count since our white damage is pretty shitty.  And as we all know our special attacks come off our mainhand.  So I wouldn't be adding in the chance to miss for the offhand.  Off hand is important to for shiv and all but from what I have observed on my own rogue, It doesnt miss.  So you really shouldnt need to worry about tons of hit maybe that %8 or so.  So if you all dont believe me and want to flame me go ahead its just a game, but before you do go run a lvl 70 instance and tell me how many times your Backstabs miss k?

Now I currently dont have good gear so dont flame me for that either as I dont get to play very often.

http://www.wowarmory.com/character-sheet.xml?r=Moon+Guard&n=Kanasta

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