"Keeping the left wrist from cupping is essential to keeping the clubface on-line during the swing. If, from a weak hold, you hinge your wrists so that the left wrist cups, you'll rotate the clubface too far open on the backswing. Only the player blessed with ultra-fast hand speed will be able to square up the face at impact from this position."
Joe Thiel, PGA Master Professional, Golf Tips Magazine

"High Handicappers execute what is called an early release. They scoop the ball at impact because they lose the lag too early in the downswing. They have a collapsed left wrist and their hands are behind the ball. As such, they suffer a tremendous loss of power and direction and end up with a very weak hit. It's necessary to hit down with a flat left wrist that's ahead of the ball at impact."
Karen Palacios-Jansen Class A LPGA Teaching Pro

"There is only one position your hands need to be in at impact if you want to hit a solid crisp shot. The back of the forward or front hand (lead) needs to be flat. No condition is as critical in the golf swing. Back wrist bent, front wrist flat - that is the key to longer golf shots at the proper height!"
Tom Jackson PGA Osterbrook G&CC (ScoreGolf Magazine)

"The flat left wrist is not only the number one alignment but also the first imperative. When the left wrist is allowed to bend during the impact interval, control of the clubface becomes difficult, if not improssible. The flat wrist allows for better control over the clubhead and clubface."
Joe Daniels, GSED, The Golfing Machine
Authorized Golf Instructor Program based on Homer Kelley's "The Golfing Machine" book what some Pro's refer to as the textbook on Golf.