We use our two tanks for locking down the frost lich people, and lowering healing load so we can use one healer out. Two healers in the dream portals. Our shadow priest goes holy to help the holy pallie. This week we saved her in 4 minutes. But Six is about the enrage timer, I think they lowered the adds health or it felt like it.

Two tanks + Focus fire imo is the way to go although I know of a group that uses AOE, they also use 1 dps 1 healer in the dream portals and two out. Our way lowers the damage done to the raid and makes the encounter go faster even if a healer makes a mistake and drops a buff.

Dreamer is allllllllllll about the stacks. It goes Stacks > Suppressors > No frost bolts/ Fire novas > other adds.