Percy also taught school for a while, giving it up to become a professional golfer in 1896. But as a player he was overshadowed by his brother Aubrey, who was much better in competition.
Percy did win the Swiss, Dutch, and Belgian Opens during the 1920s, but soon turned his attention to teaching. Among those who sought his advice were his childhood friends Vardon and Ray. Based at the exclusive golf club at St. Cloud, on the outskirts of Paris, Boomer built a reputation as a fine teacher.
Boomer was one of the first instructors to eliminate negatives from his teaching. He never told the student what he or she was doing wrong, instead focusing on what the student should feel during the motion. In the 1930s he was one of the first to employ stop-action photography to dissect what was really happening during the swings of both the average golfer and the game's champions.
He is the least published among the four inductees. Besides a three-article series in the British magazine Golf Monthly in 1941 and his book On Learning Golf, published in 1942, Boomer wrote little. But On Learning Golf received much attention even during the war and quickly sold out its first printing. It remains a ground-breaking text and is widely considered among the best books ever written on playing the game.
Boomer endeared himself to his followers when he wrote, "Everything I have ever done in golf, I have had to learn to do" -- a statement most average golfers can readily relate to.
Bibliography On Learning Golf, Alfred A. Knopf, Inc., New York, 1942
Boomer believed that learning to control the swing by feel, rather than by thought, is the only route to a sound golf game. In On Learning Golf he said, "I do not believe in trying to impart the swing in stages or by sections; from the first lesson I teach the swing complete." He insisted that as many shots as possible be played with the same fundamental movements.
Boomer listed his six essentials of the swing:
- It is essential to turn the body round to the right and then back and round to the left, without moving either way. In other words, this turning movement must be from a fixed pivot.
- It is essential to keep the arms at full stretch throughout the swing-through the backswing, the downswing, and the follow-through.
- It is essential to allow the wrists to break fully back at the top of the swing.
- It is essential to delay the actual hitting of the ball until as late in the swing as possible.
- It is essential not to tighten any muscle concerned in the reactive part of the swing (movement above the waist).
- It is essential to feel and control the swing as a whole and not to concentrate upon any part of it.
"This controlling feel is built up through the constant repetition of the correct movements," Boomer explained. "It is highly desirable that the memory should not be confused by the frequent or even occasional introduction of other and different movements -- as happens when the swing is fundamentally changed for certain shots."
THREE BRACES AT ADDRESS
"The difference between the good and the ordinary golfer is that the good one feels his shot through his address. Through his carriage and balance he feels he is set inwards and behind the back of the ball and his legs, hips, and shoulders are all braced, inside and behind the ball.
"There are three directions of brace in the correct address position. The first is the 'inwards' brace, applying to the hips, elbows, shoulders, and stomach. The second is the 'upwards' brace of our bodies, which makes us feel 'down' and firm on our feet. The third direction of brace is a twist around of our hips to the left. The right knee does not resist, so we find our left side straight and right side bowed inwards. To complete 'the set' the head and chin should be turned slightly to the right.
"If you are properly braced at address, you should feel no sensation of wanting to lift the clubhead. We should never feel that we lift the clubhead, but that we carry it back around with the body and along the ground. Feel your body carrying it back along the ground, and that the clubhead feels 'down.' "
ONE SENSATION FOR ALL SHOTS
"The reason for adopting the three braces at address (described above) is so that you will feel that you will bring the clubface square into the back of the ball, not from above, but from behind it.
"When I say that I putt as I drive, I simply mean that when I putt I feel that I roll the ball along from behind -- and I feel the drive is only an enlargement of this sensation, not something different from it.
"One sensation for all shots. I keep harping on this because it is not the knowledge of what we have to do which leaves us on the course -- it is the feel of what we want to do that is apt to evaporate unless we have built up a secure feel -- memory of how the swing operates. The only way in which we can repeat correct shots time after time is to be able to repeat the correct feel of how they are produced."
KEEP THE LEFT ARM "DOWN"
"We are frequently and wrongly told to keep our left arm straight, when we should be told to aim for the feeling of it being pushed down. If we look for that, our arm will be practically straight even at the top of our swing, because we are stretching it to obtain the down feeling.
"This is the reliable way of reaching this end, because it is conditioned and controlled by feel, not thought. Incidentally, this explains why you can be a top-class golfer even if your left arm is not straight at the top of your swing -- not the straightness but the downness is the vital factor."
SENSE THE CLUB SWINGING FROM INSIDE
"The essential feel of a good golf swing is of swinging the clubhead not directly down the line of flight, but from inside this line as the ball is approached to outside the line in the follow-through. Ignore the fact that the clubhead actually follows the line of flight through the impact area. You play golf by feel, not by fact.
"This feeling of in-to-out is intimately connected with that other feeling referred to in the address of feeling set inwards and behind the ball."
DRIVE A WEDGE
"We shall never be good golfers until we can feel that we pull the clubhead along as we swing, along, not up and down. Let us put this in another way. If I were to ask you to: 1) Drive a wedge under a door, and 2) Drive a nail into the floor, you would visualize two entirely different directions of hammerhead travel. Driving the wedge under the door is the direction we must feel at golf. The force must go along through the length of the wedge, along through the length of the ball."
TURN IN A BARREL
Boomer is best remembered for his image of swinging inside a barrel to create the sensation of a proper turn. He would ask students to imagine being inside a barrel that extended from the golfer's chest down to his knees and big enough around to allow the golfer's hips to turn freely, but no so big as to allow him to sway either forward or back.
With this image foremost in a student's mind, he can start making the proper turn, which will become memory to the body without having to remember many complex technical points.