[1.2.304] Strange items...

Your original post was "Not on a 850% skill." Don't even try to deny it, because I saw it with my two eyes.

On a 810% damage skill, no it won't. Even with a 50% stun rate, you're talking about less than a 10% dps increase, and it's more likely going to be 10%ish on most equips.

On a 810% damage skill

810%

In any case, critting for less than 20% damage? That damage will be added TO the stunned damage. And yes, the monsters will be stunned enough to make an actual difference. It's not like the monsters will NEVER EVER be stunned.
Your argument makes me think you've never played a class with a critical, but that'd be hard to belive when you have a level 164 character. The critical damage from stunning monsters wouldn't drop down from +160% damage to a measily 20% damage. It'll be stacked with the +160% damage just like SE does. If it were to happen the way you're saying, Vipers would literally be f'ucked. We would end up a shi't ton weaker.

970/810= 1.1975308641975308641975308641975 less than 20% efficiency increase.