Originally Posted by jmnk
It's not physically possible to hit a sphere (a ball) with forward tilted plane (a racket) above the equator of the sphere, and --not-- hit down on the sphere.
saying 'the racket face is slightly closed and the contact point is above the equator of the ball.' and saying 'hitting down on the ball' means exactly the same.
This sounds like a matter of semantics
. To my mind, and I suspect to most people, if you say that you are hitting down on the ball, it implies that the racket face is closed and moving in a downward direction
at impact. In the case of the serve (and most topspin g'strokes hit with a slightly closed face), the racket is not moving in a downward direction at all but is moving upward during the contact phase.
In fact, in studying slow motion videos of serves/shots hit with a slightly close face in the manner I described, the ball moves upward just after contact, not down. Take a look at the link below about 30 seconds in. This, to me, is a clear indication that we are not hitting down on the ball.