What a way to meet your son's parents! The mature dad, whom the wife, and part-time mother of the young girl's boyfriend, trusts completely, conducts a test drive of their son's young girlfriend to determine whether she is worth taking into their family or if their son should find another date after all. Judging by the video - the son's choice is approved by the whole family!
Marital sex just needs to be varied. If the couple won't do it together, then clearly they will still do it secretly each separately! I think this home variation is acceptable, in any case it is not as extraordinary as entertaining a large group of swingers. My wife and I once invited me to one of these, against her this clip is just sex puritanical family!