I've been thinking about Nadal's grip size (he apparently uses a 4-1/4) and am more and more convinced his recent problems to control the forehand have something to do with it. For a man his size, 6 feet 2 inches, this seems like a ridiculously small grip (unless he has disproportionally small hands for his size,which I doubt is the case). I am 5 feet 9 and use a 4-1/2. A 4-3/8 feels too small, though I can play with it and actually feels better on the serve. A 4-1/4 feels ridiculously small. He probably hasn't changed it since his hand was much smaller than it is today. A smaller grip makes it easier to use a lot of wrist, gives you that whippy feeling, which works fine for his heavy topspin shots, but when he wants to go for somewhat flatter shots is when he makes the mistakes. It seems reasonable to assume that the smaller the grip, the less control you have of the racket face angle with respect to the ground, and in a flat shot you need to be very precise about that angle, as your margin of error is small. Just like on a volume knob on a stereo you can regulate small variations much better with a larger knob. The angle of your racquet face meets the ball at about 90 degrees to the ground plus or minus 5-10 degrees most of the time. A single degree of difference can cause a very significant difference in where the ball lands, as much as several feet perhaps (all else being equal). I keep thinking of the stereo knob analogy. Assume a round volume control where each degree of variation represents 1 decibel of difference. Assume you are asked (blindfolded) to increase or decrease the volume by one decibel. Obviously your task is rendered easier the larger the circunference of the knob you are using. On a very small knob, the slightest movement can easily go way over 1 degree. On a larger knob. you have more length of arc to work with. You sense (rather than see) how the racquet face is aligned with respect to the ground by the feel of your grip. And this has to be much easier to do on a larger grip. Imagine playing with a grip as narrow as a pen, for example. You couln't control the racquet face angle at all. Perhaps the reason he is less erratic with the backhand is that there he has the right hand to feel the position where the racquet handle begins to fork. One of the sweatest experiences in playing tennis is to hit a flat shot with a lot of whippy wrist. If you hit it right and time it well, the speed you impart on the ball can be quite awsome compared with your regular arm shot. This whipping motion feels more confortable with thinner grips, so maybe that's why he likes it. But you need an extraordinary feel to control the angle of the racquet face. These are just idle thouhgts, but am convinced he would miss fewer forehands if he gradually increased his grip size to something more appropriate to his hand size. Maybe someone should tell him.