On a serious note, it's possible to play octaves faster than you can play notes in a scale with one finger, the thumb or the pinky/ring finger. Due to the bounce while playing an octave, and keeping your hand in position, the thumb for example can take the "lead", and the other finger follows automatically. However, after a while, the other finger "takes over", so it's kind of like a swinging pendulum or something, they kinda balance each other out, making it possible to play faster than you can play single notes with one finger.