But ideas put forth by a former pro, lifetime instructor, and author of tennis books and video is not unfounded; especially when there are several posters speaking of how the instruction worked and helped them. That is very founded. It may not always be right, since nothing is always right, but it's darned well founded. If you are struggling with a geometry proof, are you going to listen to the ones who also don't get the problem, or the ones who have solved the problem and are experiencing success with it? You seem to find comfort with the others who say the problem can't be worked that way and ignore those who demonstrate different.