"At the moment of impact the hands work not together but against each other. The left hand must bear back against the right. Immediately prior to and during the moment of the club's contact with the ball, the right hand speeds up the club head. It cannot do this if the left hand fails to offer a backward resistance against the upper end of the club handle. This back pressure of the left hand must be exerted at the moment of impact." Original Golf Fundamentals, Dunns of Musselburgh, Scotland
DUNN of Musselburgh, Scotland (1922) says : "The majority of players who fail in transmission of power do so because their left hand fails to act as a fulcrum for the right hand to strike against. The left hand has to bear back against the right.
To understand this matter, take a club in hand and press the face of it against any solid obstruction, with enough force to bend the shaft. Maintain this pressure and ask yourself, "What am I doing with the upper palm of my left hand?"
You will discover that you are very decidedly pressing the club handle backward against the forward pressure of the right hand. This back pressure of the left hand must be done at the moment of impact if you are to overcome the resistance of the ball."
ALEX SMITH of Carnoustie, Scotland (1907) says : "One further point and a most important one, although I have never seen it brought out in any of the previous textbooks. As the club comes down on the ball, do not allow the left elbow to swing out and away from the body. It must be kept back so as to allow of the "snap of the wrists" at the critical moment when the ball is struck. If the left elbow swings away an instant too soon the hands go through in advance of the club head and the result is either a slice or a loss of power.
TIMING : A favourite phrase nowadays is "timing the club," by which is meant the securing of the full power of wrists, arms and body at the moment when the actual hit is made. The phrase is a good one, but unless the coach can explain how to bring about this desirable result the mere words will not help the beginner much. My theory is that this "timing" is dependent upon keeping back the left elbow, thereby enabling the full force of the stroke to be brought into the ball."
Download : 'The Science of the Golf Swing. How The Mathematical Approach Solves The Problem of The Golf Swing' including: "It follows from what has been said above that, so far as the generation of clubhead speed is concerned, the fundamentals of the golf swing are faithfully embodied in the whirling-weight action. I do not wish to sound dogmatic but this settles for good and all the age-old controversy as to whether the golf swing is a true swing or a hit." By Dr. David Williams, D.Sc., F.I.Mech.E., F.R.A.e.S., C.Eng. Formerly Deputy Chief Scientific Officer at the Royal Aircraft Establishment, Farnborough. PELHAM BOOKS, Pelham Golf Books, Published 1969
"In a golfing sense the hands in a way really work in opposition to each other at the crucial moment, the moment that counts, that of impact between the club-head and the ball, the left arm stopping at the wrist for an infinitesimal fraction of a second as the ball is struck, accelerating the speed of the clubhead. This momentary stoppage is not discernible to the eye, but it exists just the same." Walter J. Travis
Download : "Bob DUNN possesses what is recognized as one of the most powerful drives in golf. One of the five golfing sons of a Scotch golfing father, Seymour Dunn. Yesterday, testing out new balls at the North Daytona Beach links, the pro smacked not one, but seven balls down the fairway for upwards of 325 yards." 'Daytona Beach Florida Morning Journal', Jan 13, 1939