This is just a quick tip that I received while taking a lesson a few years ago. I was working with a much more advanced player than myself and was having problems getting drives on the backhand side past him and found myself stuck in a losing pattern. The objective of the drill was simple, hit a good enough shot to get the ball past him so that I could take the 'T' position away from him and then try to keep him behind me by taking the ball on the volley. I was trying to play a hard drive down the wall all of the time and I was not able to keep it tight enough to force him to let it pass. I found myself stuck in the back court and not succeeding at all with the drill. He stopped the drill and asked me what I was trying to do. I said that I was trying to drive the ball hard down the wall past him. His reponse was simple. It is not working. You need to try something different. You are not getting the ball past me with pace so why not use height to get the ball past me. Hit it high enough that I can't volley it and will have to let it pass me.
While the example above is about trying to pass your opponent on a rail shot on the backhand side it applies to all parts of the game. If you find yourself stuck in a pattern that is not working you need to change it!