my take on the "No, same show, new drummer, can't take a chance" comment from Dylan was that it seemed he was just saying that the drummer (Gregg) was still VERY new (only having played the two Berkeley shows). it didn't seem like Bob meant it was a brand new drummer just for the SF show. just my two cents. difficult to actually confirm anything of course. also, Bobby Gregg seems to flub the into to Long Distance Operator at the SF show, maybe showing he wasn't quite up to full speed yet with the band.