I understand the healing strategy, and tried it a few times, I just magma's down the trash walking with the boss and chain healed the group near the boss to keep him alive, at times he can drop quick. The aggro from those heals seemed fine.

Everything will die from your totems easily. You might need to pickup your totems quick at times just so he doesnt die when the orb controller is fatigued

At times I chain lightninged the orb controller area and rid that area of mobs.