i should clarify: i have BoH, serenity, and blinding flash on my bar. i never find myself in the position of "oh !@$# i have to heal or bubble". because you can avoid the hard hits and position yourself away from the flames. if you stand in the fire, get hit by his charge, or get hooked and stunned, then.. you're gonna die in a2 because lots of mobs in a2 jumps at you, flies at you, shoots at you, and puts fire on the floor. so, learn how to survive without blowing defensive cooldowns as that will cause you to hit a serious wall in a2.
you're not going to face tank anything in a2, and its debatable whether or not you can do so even when 1.03 goes live. i can "tank" white mobs if they're in small groups, and i can "tank" elites if i can separate them from the pack... but for the most part i kite a few yards, cast earth ally, get off a few rotations of deadly reach, and repeat. i'm in motion for maybe 50% of the duration of the fight, unless i am fighting arcane/mortar/desecrator/plague/frozen, in which case i am in constant motion anyway.
i had a1 on farm for a while, but couldnt even get out of the canyon in a2 because my play style just wasnt right.