The boring mage of red

[Remnance]

I believe the auto attack canceling it is a mis-translation. That said, I don't think RDM auto attacks add anything meaningful to their DPS as they scale off of strength (I'm surprised they didn't go with Dex) and hit like a wet paper towel.

Yes, an auto attack will remove your dual cast proc. It is an actual game mechanic.

[Rawrz]

Yes, an auto attack will remove your dual cast proc. It is an actual game mechanic.

Except in game, it does not cancel it. Using a weapon skill or sprint are what normally cancels it.