Or else there is one single very promiscuous woman who is running up the numbers;p

Um, yer, that would be me

nah, I wish.

Actually, it seems to me that there is a tiny flaw in the argument. If the population of women is larger than the population of men (which is the case), then it is technically possible to have different averages. Just consider a planet with one single man, and 100 women, and suppose they adopt a harem-like system - the lucky guy would have an average 100 partners, while women would have to do with one little partner... The myth is safe?

See here (clip) or here (source) for a critique