" The movie has Marty say "blues riff in B" and then WHAM, the entire band is playing Johnny B. Goode like they've done so for years.  It's amazing, and as a kid, I spent a lot of time trying to figure this out.  How was it possible that everyone knew what notes to play and when to come in??  The backup guitar and drums both hit a beat at the beginning of the song without any communication whatsoever. "

― Ryan North , B^F: The Novelization Of The Feature Film