Do all those middle-aged and elderly people in the Cañon Theater deserve to see their moment of rock & roll glory told onstage? Absolutely. Does Bill Graham symbolize enough of that glory to warrant a one-man show? Of course. Graham is a more-than-suitable example of the American achiever with the ruinous Midas touch who dies before his time. Yet this play soon veers off into what-were-they-thinking? territory. ”Greed and sickness had taken over,“ Greenfield has his Bill Graham say about the rock business at one point. The fact that the line is delivered with a completely straight face shows how little this Graham understands himself.