I don't think anyone has mentioned

RATED X (2000).

This Showtime film, directed by Emilio Estavez about the infamous Mitchell
Bros. (Behind the Green Door), features Peter Bogdanovich as a particularly
nasty example of a film professor, who berates Jim Mitchell (at San Francisco
State?) for producing pornography, rather than art.  In point of fact,
Mitchell's film is - from what we see- a typical 60s hippie film with a girl
dancing topless in a park.


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University of Alabama: http://www.tcf.ua.edu