My coach tells me that, when I hit the ball into the net on my serve, I am not keeping my eyes on the ball when I hit it, and I am dropping my head. if I see th eball hit th enet, I'm doing something wrong. Yet I saw Venus double fault a few times by hitting the ball into the net in her match with Jelena today. I refuse to believe that Venus's mechanics are not perfect. So what is going on here?