This is not true. See Berdych against Murray on clay especially.
This isn't a great example. Murray's shots fail to effectively penetrate most clay courts, so the ball sits up. Berdych benefits from the extra time to set up on most of his shots, and he has the added firepower to make the property of the court negligible. It doesn't necessarily translate the same on other surfaces.
In any case, I agree that it's a bit too simple to suggest that you need only make him play to beat him.