That is the most important five inches in golf. Sound judgement is as important and easier to acquire, for someone seeking to improve, than learning to swing a club like Rory McIlroy. The next most important five inches in golf is the two and a half inches before, and the two and a half inches past, the golf ball. If you can have your clubface square to the target line during that five inches, a good shot must result. It is a scientific certainty, barring a strong wind, or mud on the ball, that a ball struck with a square clubface travelling down the target line will fly straight.
That being the case, it is a wonder to me that so little emphasis seems to be placed on this five inches by many modern teachers of the game. The ability to consistently square the clubface and move it down the target line is the key to good ball striking. A great swing, with a full shoulder turn, good extension, straight left arm, flexed right knee, etc.; means nothing if the clubface is not square to the target when the ball is struck. If the clubface is misaligned, a great swing will produce a solid shot straight into the trees, or out of bounds.
Tom Watson, in an interview on the subject of Byron Nelson, said that Nelson kept his clubface square to the target line for twelve inches. He further stated that Ben Hogan had his face squared for six inches and Sam Snead had his square for five inches, directly before, during and after impact. Moe Norman, who is often regarded as the greatest ball striker ever, claimed he kept his clubface square for twenty two inches past the ball. Whether that was actually proven by the camera, I don't know, but the important thing is that this was what Moe felt he was doing, and why he believed he was the greatest striker of the ball; because he had found a way to keep his club square to the target line well before and well after the ball was struck. The end result for him were laser-straight golf shots, one after the other.
My intention, from now on, is to make this my focus, that five or so inches before and after impact. A practice drill used by Moe Norman, was to place quarters or tees in front of, and directly behind the ball, along the target line, or intended line of flight, and to work on keeping the clubface square to the target through that zone. I plan to start with that all-important five inches, and work towards twenty two. The longer the clubface is square, the more consistent my shots will be. I may sacrifice some distance, but the woods are full of long drivers.
The easiest way to ensure a square clubface through the hitting zone according to Bobby Jones, Sam Snead, Byron Nelson, Moe Norman and even Ben Hogan is to focus on the back of the left hand pulling the club through impact down the target line. I intend to keep working on this. It has worked very well for me and I highly recommend that you try it. Remember, this tip doesn't come from me, a tip from me and half a dollar wouldn't buy you a coffee. This information comes from the greatest ball strikers in history. Focus on that five inches. Those are really the only five inches that count in golf; other than the five inches between your ears.