If you’ve watched “The Karate Kid,” you’re familiar with the story: Mr. Miyagi, the wise old Japanese maintenance man, prepares Daniel for a Karate championship in record time. His method? Countless hours of repetitive labor, which secretly mimic karate moves. After many days of mindless “wax on, wax off,” Daniel finds that he’s mastered the basic moves of Karate—all because of those endless hours of repetition. But is mindless repetition really the best way to practice?