John Lennon's marrying Yoko was advanced, though probably not for the reason you think. He loved her because she was interesting, not because she was beautiful (though he found her attractive). Same goes with Paul McCartney and Linda. These guys could have any woman they wanted but they didn't choose movie stars or models. The overt artist will always go for the trophy girlfriend or wife (if he's a man). So what of Mick Jagger and David Bowie's marriage? Well, I think Jerry Hall was more than just your average model, but there is still a certain amount of overtness in that choice. But marrying Iman is not overt for David Bowie. Why? Because she's Iman.
I'll probably talk more about how choice of mate relates to overtness/advancement in the future.