Would Duality working with combo effects be a bad idea?

[Sevyrr]

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

The 966 crit?

You lose a Duality AE for some more non Duality AE's.

Looks zero sum to me.

If you lose a Duality AE for a Duality AC, that's 640 potency swapped for 560, so -80.
The question is how many AC's would you then be changing to AE? At 2, you're gaining 80 potency, so as you say a zero sum. If you'd manage more than two before the next Duality was up, then I suppose you're "gaining" raw potency, but not by an awfully noticable amount.