Principle of the advise.
I would like to explain the thoughts behind the upper part of the advisor, which advises the right SW:
The advise is based on the fact that a player needs more force when he has to accelerate the racquet more.
Someone who makes his back swing very early can move his racquet backwards slowly because he has a lot of time to do that.
Someone makes his backswing very late (after the bounce) needs much more force to accelerate his racquet because he has less time to bring it around.
So the first player can easily play with a higher SW without needing much force, it will cost the second player a lot of power to play with a high SW.
Compare Söderling with Nadal or even better (for the oldies) with Steffie Graf.
It is logic that stronger and older players can play with higher SW’s easier than tiny built youngsters. That is why you can enter a build and age of the player.