This is a Pyramid *myth* mind you. I didn't make this up, but rather definitely heard it from someone, who could have been: Hattie, Bobby, Tanya, Sister herself, Mark Oates (probably him come to think), etc. I wasn't there.
But the idea was that there was some kind of big night, the first of some sort, and Sister didn't let on what the first tune would be until they opened the back room to the strains of