The difference between commentaries from Film Historians and Film Critics is that the former talk history, while the latter talk opinion. Unfortunately, while PENNIES is a heavily conceptual film, it's still a one-note concept (characters lip-synch old tunes), so Rainer doesn't have a lot to talk about. In acknowledgement of this, there are a couple of looooong pauses (I thought the audio had somehow switched over to the original track the first time), and there's not much described in the commentary that you couldn't see or figure out for yourself. This would have worked better with a couple of others on board - a member of the cast/crew for personal anecdotes, and a historian for details.