ForehandophobiaSyndrome
The forehand is the most versatile shot in the game. It is, therefore, the most treacherous. On any given day, your forehand can be your best friend or your worst enemy. For the majority of you, the forehand is your most natural stroke. It seems to put superior power, control, spin and touch at your fingertips. But it is also a mercurial trickster, whose siren call tempts you to overhit, under-hit and invent shots on the fly.
The advantage of the forehand comes from the muscles that you use to hit the shot. The forehand agonist muscles, the muscles responsible for power, control and spin, are far stronger than the antagonist muscles that counterbalance them. The biceps are stronger than the triceps. The flexor-pronator group in the forearm is stronger than the extensor-supinator group. The pectoralis muscle and anterior rotator cuff in the shoulder are stronger than the teres minor and trapezius. You were built to hit forehands. The dominance of the agonist muscles results in a natural ability to add impulse to the ball for control and spin. But, as in life, the forehand's greatest strengths are also its greatest weaknesses. There is a strong tendency on the forehand side to hit through the ball, e.g., to muscle the ball. This is decidedly not how we need to impart control and extra spin to the ball (see Push Syndrome and Hot Shoulder Syndrome.) Driving through the ball does impart directional control, but unless the all the stars align, that impulse will be in the wrong direction.
Spindirection
More than any other stroke, the forehand conveys an illusion of control. If we drive through a ball, agonist muscles bulging with affirmative effort, and if it so happens that the direction we are pushing the racket coincidentally coincides with the direction we want the ball to go, then everything will be fine, and the strike will be successful. We will also enjoy the satisfaction that comes from knowing exactly where the ball is going because we forced it go there. There is a lovely simplicity about it all; racket goes low-to-high with the face pointing along the line of flight, and the ball follows suit. That is exactly how I was taught to hit a tennis ball fifty years ago, and elements of that technique are still being taught to beginners today. I even know some very talented players who still hit through the ball with their forehands with some success. Problems with hitting through the ball arise when you try to add spin, or whenever the ball ends up someplace that does not fall on a direct line between the end of your backswing and your target. In both of those cases, the line along which you are driving the racked does not correspond with a line extending from the point of contact to the target: in short, you are driving the ball in the wrong direction! Thus, to hit a flat forehand, you must carefully match your backswing to the expected point of contact. A backswing that is too low will result in a long ball and too high will result in a netted ball. These restrictions are too confining for most playing professionals: You have to go back to Jimmy Conners to find a pro who hits a flat forehand. Based on the preceding discussion it is clear why Conners had to get so low to the ball. His lack of topspin on his forehand explains why he had to keep his forehands so close to the top of the net strap.
Curing Forhandophobia
The key to the cure is topspin. The power of the biceps and flexor-pronator muscles make it possible to generate more topspin on the forehand than on any other stroke. If you aren't devoting half of your power to creating topspin, then you are trying to walk a tiger on a cardboard leash. Only extreme topspin can keep a full swinging topspin in bounds and out of the net.