Quite a few of my students play with racquets that I think are too heavy and grips that are too large. It's a sensitive issue. The player gets used to the weight of the racquet and may be reluctant to change (or maybe can't afford to change). It feels more difficult for me to help them get more racquet speed and be quicker around the net when the racquet may be affecting their technique.
I started with a wooden racquet and got good racquet speed since I had a whippy forehand and serve (and very good technique). The racquet weight may have prevented me from developing a better one handed backhand, since it's harder to rotate and keep the racquet steady (especially when you are 14 years old).
I'm open for discussion about racquet weight. What are you experiences with making changes or adjusting to different weight racquets?