[cdavisdb]

I don't think it is quite that simple in practice. All those things affect planning speed, but when its sloppy, the forces on the boat keep changing rapidly. If you don't have the low end torque to maintain prop rpm, what happens is: its sloppy and you want to plane slowly, so you increase throttle until the boat gets up and planes, then its going to fast for comfort, so you reduce throttle a little to slow down a little, but then the boat falls off a plane and you're going 6 knots again, repeat. If you have sufficient torque, you can hold the boat on a plane at a slow and more comfortable speed.