One of the main problems with this boss is the dmg boost the debuff gives to your DPSers. When they have that buff it's easy for them to kill the next energy spark and get 2 debuffs, effectively making them impossible to heal in addition to your tank. One trick i do is just watch my Dpsers and when the first one gets the debuff, turn him around so he can't dps anything. The next spark that comes out will die to another toon. Once you have two debuffs you might just want to hold off on dps to let the debuffs leave. With practice, you can time it so all your dps have 1 debuff each , then when the boss goes crazy just turn thema ll around and level the boss instantly.

When you do the slow and steady approach, and let all the debuffs wear off, that last little bit of hp is hard to take down before he kills everyone with his exploding AOE since your DPS isn't jacked up with the energy debuff.

Use slow and steady for the first few energy adds, then the last 3 use the 'turn the toon with the debuff around' approach until all 3 toons have it then face the boss and level him.