The Rules are as clear as mud on this issue. They say that if you touch the ball and it oscillates but does not "move" from its "original position" no foul has been comitted and you can play the ball as it lies without penalty. However, if you exert enough force on a ball to make it oscillate you have started the purely innocent pelota on a Newtonian journey involving force, mass, acceleration and deceleration, friction and gravity and only rocket scientists know what other forces, all combining to absolutely make it impossible that the ball will not have ended up its journey in exactly the "same position" as it started. It may look like the same place, but it ain't, surely on the molecular level and probably not either on whatever level current HD technology can record and measure. The rule should be changed to "If you touch a ball with your club or any part of you or your clothing (even if just in adressing the ball), there is a one stroke penalty (or more simply 'you have played a stroke'). If the ball moves as a result, you MUST play it from there, as you have, in fact, taken a stroke.
Or something of that ilk.......