Jim.
I know you're thinking as an instructor, and I get that. I agree that more power can be an issue, just watching the youngsters with the high performance crotch-rockets and sports cars/sedans and how much they seem to think it's their "right" to break traffic laws.
At the same time, I can see where running a .46 is also a good thing. If you're teaching someone to fly, isn't it a good thing to teach THROTTLE MANAGEMENT? While a smaller engine WILL WORK, you have to run it harder to get the plane to perform more advanced things during the later stages of training when just doing circuits of the pattern, touch and gos, figure 8s and the like get to the point of driving the student insane due to repetition(no, this isn't a bad thing either). Having to be more aware of throttle settings and how it affects what the plane is doing is something that is a good thing, isn't it? To me, having "marginal power", like having a four cylinder engine in a full sized car, isn't going to to really teach that. While the four popper will move the car and it's contents along at the speed limit, when you need that extra "punch" to avoid something, it's not going to be there since you already have the engine pretty much maxed out. Just like knowing how and when to use a rudder, knowing how to EFFECTIVELY use the throttle is something every new trainee should be taught, not just that you need to go to full throttle to get the plane into the air