I have a horror story about grips. Being a munchkin, I use a 4 1/4; when from time to time I would go up to a 4 3/8 I could use it, but finally realized that the smaller one suited me better.
I got into the habit of customizing my grips: whenever I bought a new stick, I would take off the grip that came with it, wrap sticky black tape around the plastic butt, and then apply an overgrip. I love the feel--it's like I can almost grip the ridges.
Well, I got a new racquet (Babolat) a couple of years ago, and the grip that came with it was "cushioned," which was nice and soft, but felt too big in my hand even though it was my size. But having a doubles match that day, I played with it anyway. My first mistake. On hitting a high forehand volley that had got past me a little bit, the racquet torqued in my hand and bent a couple of fingers back, way back. I must have torn or badly stretched some tendons, because I had no strength in that part of my hand for months--couldn't lift anything, couldn't press my finger & thumb together. Even after a year, I could still feel that weakness a little. It's pretty much healed now.
But I will never again use a racquet with a grip that feels too big. Needless to say, I have customized that one and now it is just fine.
Thanks for letting me "share."