I suspect that there would also be more engine power available to drive the main rotor if not having to send it down the back with the associated loses. When I first read the thread I wondered if they would shut down one or multiple/all of the fans in the cruise. I don't like it visually but guess its an idea that is inevitable given the advances in electric motors, the multiple fans would provide redundancy. And I agree with Charles, main rotor will require anti-torque