This film could only have been made in the 70's during a very brief period in porn and the general population of the US when it was possible to make an erotic film of more than fake moans and money shots because porn actually for a brief few years had a potentially wide outlet both in terms of who would go see them and where they could be shown.
I'm a woman and I first saw it at the University of Minnesota where they were going to show it in a 1000 seat theatre one time for one night. (Try getting any porn onto a campus now.) They added two more showing to that night and then kept it around for a month or so with 3 shows on Fri and Sat. All the major papers in Mpls and St. Paul accepted ads back then for porn and X rated movies in addition to all the weeklies and student paper. Believe it or not but the reception of Deep Throat (a lousy movie IMHO) being so wide and broad it was made this possible. (Most major papers won't even accept an advert for a NC-17 movie nowadays.)
It was wonderful, the audience was made of both sexes, young and old and probably 60% couples and the film was loved. Women walked out smiling and hot. What I liked about it was the women actually looked liked they were having fun, and the sex was shot with the men actually satisfying women. (Go see Showgirls for a movie which in the major sex scene the actress looked like she was having a epileptic fit.) Additionally, there was always a tenderness exhibited during all "major" scenes which was unheard of before and after this period. For instance bodies got played with, there was cuddling after a few hour stand?? Revolutionary, toss in the humour and ending and well -- what more could you ask for.
But what was really wonderful was that so many of us women finally had an erotic movie that we could thoroughly enjoy on all levels just like the men. For the last 30 years I been telling everyone this was the best, the ultimate porn flick for everyone. Such a shame it's not one of a large group.