As said in title, the difficulty of healing in a heroics is now solely dependent on the performance of the group. If the dps isn't retarded and doesn't stand in stuff on the ground or hit something that has thorns (DAMN YOU TOL'VIRRRR!!!!!!) healing and mana pool would be pretty good.

However if dps is crappy or doesn't understand what CC is then you will definitely see a huge dent in your mana pool. It's back to the old days where you had to do heroics via guild runs because most pugs utterly fail.
Edited by Holyvengence on 12/13/2010 12:14 PM PST