I've not had that happen at all.

Also with bane's increased range my old method of baning twice on the spiders and spiders+rooks from certain targets is no longer reliable. More often than not I end up with one-three targets without any DoTs at all on them. So what I've instead begun to do is tab over to one that didn't get any, apply all 3 and energy drain, tab to the last one, all 3 and fester, then pop M2 and use blizz2 until my MP is down to 2400 or less and use Aetherflow. Probably not needed for phase 1 since we were always several seconds ahead. I try and double bane phase 4 still and then hunt down any that didn't get baned and do the same. More MP efficient per damage imo. Though if you have a bard who can toss up ballad its less to worry about