Mana while not tanking?

[melange]

I am curious how people are getting 2 mins. In fights where you have to OT with the intent of being behind the MT in threat and ahead of the other DPS : 1 min and there goes your mana cause you have to use all your threat abilities. Pot might give you a little bit more.

[Sabindeus]

Using Seal of Blood I can keep going for quite a while before OOMing...