This is what i do.
have my mage and lock each cast one cast at the boss, let them die.
Pickup aggro with the pally. shaman dps, druid heal... in comes insanity 1. since the druid just casts nourish on everyone its damn near impossible to kill adds. So i just self-heal a bit, wait out the 2 minutes.... then make sure the pally picks up the aggro again. In comes phase 2 of insanity, rinse and repeat till finished.