Have you heard of Glen Mills? How about Patrick Mouratoglou? Surely you’ve heard of Butch Harmon? They are the coaches of some of the world’s most dominant athletes; Usain Bolt, Serena Williams and Tiger Woods respectively. These three athletes, in their prime, were/are nearly unbeatable. Not only are they the greatest of their era, they are arguably the best the world has ever seen in their chosen sports.