tried it on heroic again last night, this time on my druid as a healer. That place is really rough, 2nd boss (vexxelus) is a bitch of a fight. The adds he spawns deal so much damage with their chain lightning so quickly that it was very hard to heal through. We got him on 2nd attempt with 3 of us dead. The 3rd boss (priestess, aka 5v5 arena fight) we kept wiping on due to lack of any real CC and the mage we decided to alt in (one of our alts) sadly was not attuned so we called it after a few wipes. I will say that if you can do vexxelus then kael'thas is a piece of cake even on heroic. The 3rd boss just needs some mad Dips in order to drop one of the mobs right at the start (such as the warrior).

The run before the healer got the healing trinket off third boss and one interesting point of this is that the charges go through mortal strike. so if you have the full 20 charges it will heal the target for 2k hp no matter what, kind of nice