The Hidden Forest

If you have zerker 2.0 equipped is there any need for dark fire, dark frost, dark thunder focus?

http://www.thehiddenforest.org/webtools ... hp?id=8951 is the worn effect on epic 2.0 and its +150% spell dmg, dark foci is 93%.

The effect stacks with the dark lines, so it's more damage having it equipped.

They are both worn effects and both use slot 1 for the spell dmg boost, that tells me they wouldn't stack.