The notion of women controlling the "supply of sex" comes fairly easy, supply and demand and whatnot.
But what of this commitment notion? Sure, top dog men can get sex pretty easy, and wait their asses on locking up someone while having fun, but these men are 10% of the total amount, not a representative sample. And while we're at it, why women can't ask themselves if they want something more? Even the top dogs have to make moves if they want casual sex, it doesn't fall on their laps that easy.