Todd Johnston told me a story about Phish, which he read in Nubar Alexanian‘s book, Where Music Comes From. When the band practices, one member will start riffing, then the other ones will join in one-by-one, all with their eyes closed. When a band member feels like they’re all in sync, he yells, “Hey!” If all the members yell at the same time, the band is collaborating. (GFT)