Would Duality working with combo effects be a bad idea?

[Viridiana]

It makes building for critical hit rate kind of disappointing, considering that at high numbers with i210 gear (my ninja gear chart ends up with 966 critical hit rate at current BiS without Mistbreak) you're approaching +100% damage, meaning a critical hit pretty much gives you that duality bonus anyway.

That's only, like, +60% damage, though.