UA, Dots, grab more, Dots, grab more, Dots, Fearbomb, regen and laugh as you pick the phat lootz off the corpse. UA has a 1.5 or 2 second casting time. You can't do that while moving. So, only against the first one unless you know they won't be hitting you for enough to make the interruption count against you.

The other thing is, Fear is your friend. Even if you are low on health you do not have to wait for regen if you have enough mana to cast Fear + a few Dots + Drain Life. DoT, Fear and Drain Life. Do that twice and you've used the time you would have spent eating and drinking to regenerate off killing things.

Also, the more Affliction effects you have stacked the more powerful Drain Life becomes. 5% more powerful per DoT. Oh yes, 36 yard range too!