What sight does O'Connell describe seeing in Glendale and what significance does he find in the sight?

While stopped a traffic light one day in Glendale, O'Connell noticed a man with a beard and long hair who was wearing headphones. The man was dancing with wild abandon and seemed to take no notice of anything going on around him. O'Connell saw a purity and an exuberance in the man's actions, causing him to wonder if there is "some vast collective of lone ecstatic dancers" (131) in the world.