Porn professionals are the real instructional therapists here. They've been hired by Dr. Michael Perry to imitate coition in all its diversity. Zarina and Monty are his models for textbook genital partnership. They discharge themselves admirably in all 10 positions covered, including "sideways," "scissors," "man standing," "man kneeling" and even get a hand from Charlene in the "threeway." Dr. Perry appears to have his credentials in order. As a licensed sexpert to the good people of Encino, California and with numerous guest spots on the Larry King/Geraldo circuit under his belt, his fieldwork in the erogenous zones should mark him as prime guru material for the masses.

His video creation is, disappointingly, purely visual. The doc opts for very minimal explanatory narration, giving the impression that he is withholding years of insight. Throughout the myriad variations he lends couples no advice on how to shift smoothly from one contortion to the next. Several of his advanced positions belong back in the basic workshop - "69" and "woman on top" should be on everyone's top 10 list. And he may also have erred in his decision to tape the couples in the same over-lit manner characteristic of graphic porn. This serves to decrease the sense of intimacy and may harden the product in the eyes of sensitive couples. Certainly there's a large berth of viewers who just want to have a good time and pick up a few pointers, but they can glean positions from a four-hour hardcore compilation more enjoyably.