I played the mastermind in CoV sometime ago. I am just thinking you may roll a mastermind no matter if you dual-box or multi-box. Surely it will be extremely laggy, but there is no need to control anything coz you can set your pets to aggressive. I used to do this with a friend that does AOE heal. There's really nothing we need to target, we just spam our heals.

I could even remember doing the trial missions that the whole team were mastermind players. It was messy but things died in a second.