I have written the idea on this site on many, many occasions regarding the high ball over the net which keeps the opponent pinned to the baseline, usually well beyond it. You only have to watch the French Open tennis highlights to realize that net skimming is only a naïve student's perception of how tennis should be played.
The loop on the ball hit by both Novak and Rafa in their semi final is proof that a high net clearance is not only a safe way of playing tennis but it is also a way to test your opponent.
At a young age kids can get away with heavy topspin without driving the ball because not too many kids own the ability to climb over a high ball.
It's not to say that a kid doesn't need to learn to flatten the ball out but while rallying it is almost a pointless exercise to keep driving the ball flat, for two reasons. One, it will take too much physical energy that will ultimately take it's toll mentally due to the fact that it does not take an opponent out of their comfort zone. Two, it is not safe play due to the lack of margin for error, simple.
Anyone who is learning the game needs variety of shot selection and watching the World's best players implementing just that is refreshing to say the least. Clay court tennis is of course a slower type of style however it is a surface that can develop a smart tennis player with time to think about tactics. Playing on clay develops a tennis brain that faster surfaces do not.
You only have to look at the way in which drop shots are hit regularly on clay as to how a player is looking at finishing the point rather than waiting 40 shots for their opponent to miss. Drop shots are hit when the opponent is deep in the court, obviously, that's where the heavy, high topspin ball has merit.
Anyone who is learning the game and does not own both the drive and the looped ball does not own enough variety to bother the better players. It is a proven fact that driving a tennis ball on every shot is a fallacy thought up by misinformed kids and uneducated tennis coaches who themselves lack variety of thought.
Tune in to this year's French Open and see for yourself..........