An ittf umpire showed me how. The tension is adjusted after you hang plastic measuring device in the middle and then you measure or adjust the height. Side parts are also measured for the height.
Probably you need to let him practice looping the ball at late timing or when the ball goes down so that he will brush the area more. Also, why not let him do ball bouncing on the racket? Maybe you can be creative and cut a 3x4 square inch rubber and he would practice bouncing the ball on that...
Nobody said that pros do not hit the sides. If you read the context clearly it talks about the area consistent of being in contact with the ball that is why it erodes but does not mean that they do not hit any other part of the racket.
Basing on Mizutani's rubber eroding, the area is about 2.5 inches by 2.5 inches. You would see the pips as the topsheet is eroded and this is just with 1 week usage of tenergy.
How much is a sheet of textreme? The blades look good. I assume they will play good because they have compositions similar to popular blades. Suggestion though why not make some of the dark layers in the handle be darker so that they can make more contrast to the light layer and will look more...
I have seen jun mizutani's tenergy and the eroded part is just about 2-3 square inches but again he is a pro. The more you develop your contact and brush, the more accurate the surface area and smaller it gets
2 things:
1. Practice situational points using your backhand and also the combinations.
2. Force yourself to apply it in a match and not be afraid of losing points
Feel ax is like a softer viscaria. Medium and medium hard rubbers goes well with it. I have used hurricane 3, vega asia df, omega vii series on this blade and it was good. The ax is not picky over rubbers.