we do not understand each other. I agree with what you say. you do not take into account the different game levels.
the board is only used to play topspin against the block and in forehand and backhand combinations if you have two boards. the board doesn't offer other options, that's why I quoted multiball.
I would not question the bounce plate at all. As a basic routine, it is excellent.
You are right, we don't understand each other. Because all I'm saying is, the rebound board is helpful because it provides feedback, anything you learn from it is because of the feedback, it's called a rebound (return) board, you get feedback from the ball it rebounds (returns) to you, that's why it is helpful. It has nothing to do with your level, because all it does is bounce the ball back to you, where the spin and speed of the ball is due to your input, and the type of rubber you put on the board. That is, if it returns a ball with lots of spin, that's because you gave it lots of spin, if it bounced off the table, it's because you hitting too hard, or added unwanted spin on the ball, and that's how you learn, from what the ball does that is returned to you by the board, not from just hitting the ball and see where it lands. And I have no idea why you want to bring multi-ball into this discussion, as it has nothing to do with the board at all, if you want to compare it would actually be single-ball practice as the board is meant to be a replacement for a coach/player that blocks your ball back to you.
Also, you are wrong that the board can only be used to practice topspin, it can be used to practice short game pushes as well.