It seems to me that the point is to have a controllable power system that has enough drive to push the plane through the maneuvers and enough reserve power to handle bad conditions. How you get there isn't the primary question. A big engine in a small plane is one way. A very light larger plane can work. Like a lot of things, it's the combination of air frame, power and setup. Paul Walker, in his electric setup, is flying a 750 square inch plane with the equivalent of a .90 in the nose. The motor is choked back and uses less than half the battery charge for a flight. The plane is obscenely light. It's the same concept; a superior, light airframe and great gobs of reserve power that is controllable.