Originally Posted by Limpinhitter
According to Braden, the pros hit much higher over the net than most observers realize. To my recollection, Braden said that Connors (who hit very hard, flat, penetrating groundies), hit 4-5 feet over the net, and Borg who hit heavy, looping, topspin groundies), hit 8-10 over the net.
Having said that, IMO, targeting height over the net is the only way to effectively hit the depth you are trying to achieve.
I saw Borg play close up, once - he did hit it quite high during rallies, but not 8-10 feet higher than the net. It was at Wimbledon so maybe the grass made him hit lower, but what I saw was probably up to 4-5 feet over the net max.