Scott Hancock is a software engineer in Colorado with twenty-five years of golf behind him, a current 8 handicap, and a peak of 6 he intends to see again. After an expensive garage-simulator winter made him measurably worse, he rebuilt his improvement around strokes-gained data and motor-learning research — first as a personal system, then as this book, and then as the companion platform. He has twin sons who recently took up the game with none of his accumulated swing thoughts, which he reports is both beautiful and mildly infuriating.