[airair]

It almost sounds like the matematician speaks of dual horizontal hinge action. The vertical hinge pin. Add some debth and roll and you're on the inclined plane.

If you want to put back spin on the ball you have to contact the ball above it's equator. Usually that means serious topping. But it can happen with a driver from time to time. the ball will then carry some 30 yards before it dives into whatever is in the ground.

You can also put top spin on the ball with a putter - with moderate loft and hands ahead of the ball at impact. This also means hitting the ball down into the ground. The said advantage of doing this is that you get topspin right away. If you use the loft of the putter, it will have a small carry, a little back spin and then the ball will skid for short stretch before it gets its true roll (which is the same as top spin).

Top spin putting seems to be fashion these days. But there are many putting experts who advocates hitting up on the ball with a putter - and that is doing the opposite. I've tested this from the rough. And at least from outside the green you get much better distance control if you hit down on the ball and get the ball rolling right away.

Boomer has a whole chapter on a somewhat different lesson he gave to this mathematician. (P.187 - 195)

More on Boomer:
http://www.golf.com/golf/instruction...565327,00.html