Originally Posted by anubis
Less power, less trampoline effect. If you string really tight, you can swing as fast as you want and still keep the ball in play. But *you* have to generate the pace -- the strings won't help anymore. If you swing slowly, the ball doesn't go very far. But it's also really nice at the net when you're volleying: it's a lot easier to keep a high-pace ball in play with a volley.
I feel that this post is very accurate, although according to many on this site they claim that the same or even better control can be had through low tension.