Discovered yesterday,
Il post my character later this evening when i get off work.

With chanter I had full buffs up and noticed that when i moved my cursor over the auto attack toggle button I would see an additional round of attack trigger on an enemy. If i moved my cursor over it as fast as i could over and over mobs in the hundreds of thousands of hps in hell would die in seconds!
But that alone doesnt make you unkillable in hell.... when you pause the game you can still do it. So mobs can't attack while you kill them. In short you could get a chanter to lvl 99 hc hell complete in less than a day.

Sounds pretty awesome. I'll see if I can get that fixed up soon.