You get +x% critical damage based on the critical multiplier of the weapon from the crit itself, and then an additional +x% based on the critical multiplier from backstab. So it may not look like a huge jump, since it'll probably only be about a 25% or 33% increase, but oh man it makes a difference. Add on Flesh Sacrifice, and Rogues have burst like no other.
I look at what you wrote and have come to the conclusion that you are smarter then me, i will take your word that enrage actiully works with backstab and you get more damage.
