Mr. Schoenstein is a humorist of modest stance and uneven timing, without the blinding ego or style that keeps the Miens and Perelmans afloat, but he always manages a few offhand funnies and this raunchy view of the middle-aged sex/smut scene offers some mild amusement. Urged on by a father's responsibility to answer his daughter's query about copulation -- does everyone mate the same? -- Schoenstein the researcher does the scene from the ""Oo-La-La Singles Mini Weekend"" at the Concord Hotel to porn films from which he is ejected (""I'm writing a book for St. Martin's Press."" ""This ain't no place to be writin' a religious book""), a prostitute interview ("". . . go talk to your wife""), topless massage and a mouthful of Mennen, to the big time--swinging clubs and the nudist gala Super Bowl. An erratic performance in the Masters & Johnson open.