I think something that I hate even more than the goddamn darkness, is that it's damn near impossible to get a cast off if you get so much as breathed on. I don't mind a chance to be interrupted, but the channeling skill is all but useless.
Last night, I died twice after I tried to root a SoW'd mob TWELVE times and TEN times, respectively. If you don't play the little mini game of starting your cast immediately after getting hit and hoping it goes off between attacks, you're fucked. Heaven forbid you try to cast on a hasted mob standing in your face.
Jesus. Fucking. Christ.