Isn't it just a bit suspect to say that these songs "share certain core concepts as though reflecting cross-germination of ideas"? The songs are all about women who are abandoned by lovers, or preganant and abandoned by lovers. It would seem to me that is less a "core concept" which would spread and "cross germinate" than a part of the human condition which has always been there, creates an emotional response, and sois always likely to give rise to songs.

Aren't we over-intellectualizing all this by calling it a "concept" -- let alone a "core concept" (which might "cross-germinate" unless closely watched)?