Unlike standard clicking which relies on repetitive flexion of the index finger, butterfly clicking coordinates the flexor digitorum superficialis tendons of both the index and middle fingers. By staggering strikes in an alternating left-right-left-right gallop:
Each finger has twice as much time to reset its upward stroke while the other finger is actuating the switch down. This mechanical efficiency doubles the effective input frequency without subjecting your forearm muscles to the high-frequency isometric tension required by jitter clicking.