DPSing the boss is not an issue. Surviving the insanity phase is. I have to be doing something wrong or overlooking a key element to the fight.

My team consists of a pally tank, priest healer 2 elemental shamans and 1 mage. All are 75-76.

I have tried different targeting and assist macros with no success.

My first question is ...
Does each toon have to kill the rest of the members of their party in order to leave the insanity phase faster? My priest and pally can kill anything. My priest normally just gets murdered here.

Should I be targeting certain evil twins to kill first? If so who and how do I target them?