As my age increased, and my knees got worse, I moved down to 15 and then to 14#. Each move proved to hit weaker. Also I noticed I had to have a more "perfect" hit to strike. I finally figured out with the lighter balls I was "overthrowing" them. Got both knees replaced, went back to 16# stuff. Timing came back, didn't force the ball any more. The old timing thing "wait for the ball" came back. There are going to be exceptions, but I feel like you should use a weight you can't force through the down swing.