“Sometime in the 1940s, though, American golfers began to overemphasize and complicate swing mechanics. They began to forget the wisdom that Stewart Maiden passed along to Bobby Jones and that Walter Hagen and Sam Snead discovered for themselves. This was not, of course, true everywhere. Golf is a sport of individuals and everyone had his own approach to the game. Teachers like Harvey Penick never stopped imparting sound principles about the mental side of golf. But they became a minority.”
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Bob Rotella, Golf Is Not a Game of Perfect (1997)