Ditto for us too. We just wiped, wen't back and barely got any elite spawns on the kill.

Basically what you need to do is to be constantly on the move and stop to cast/channel longer times only when the targeting circle is up somewhere else. The damage seems to lock in quickly after you get targeted and will hit you regardless how far you get after that. Yes I know it's a pain for some specs/classes, but that's how you can avoid the lightning.

EDIT: Started testing Wave now and absolutely no procs at all. Definitely bugged for Wave. The loss isn't massive enough that I'd say TK is dead though. While it does have an impact on our aoe burst capability, I'd say the hit on sustained dps is marginal at best.