It's usually not that bad if you have a decent group. But I've noticed most people in naxx epics (henceforth known as lololpics) get overly cocky and try to pull everything.
In one group we had a shaman healer. The other had a priest. The priest couldn't outheal the damage, which is okay I guess. But he was cocky as smurf at the same time.
The shaman was just TERRIBLE. And there was a warlock in that group that was complaining about me not being stacked up. When I was standing right next to him while being at minimum range for being a hunter.
He actually told me to move closer.
So I meleed.