Mac, I'm well aware of the great Louis Jordan and in his era songwriter/singers were definitely a presence, but I think they were the minority, as the extension of Tin Pan Alley wrote most of the popular songs.

Whether it was Cole Porter, Harold Arlen, Yip Harburg, Irving Mills, the Gershwin Brothers, Lerner & Lowe, Rogers & Hart and so on, my impression is that the majority of pop songs were recorded by performers and written by professional songwriters.

This extended into the early Rock Era with the extension of the Brill Building era and all the wonderful songwriters like Leiber & Stoller, King & Goffin, Otis Blackwell, Doc Pomus, Willie Dixon, Hayes & Porter, Mann & Weil and so on.

During all these eras the professional songwriter and the professional singers of mainstream pop music were the majority, but coexisted with the singer/songwriter combination. And it didn't seem important that Sinatra or Presley didn't write their songs and others did.

R&B, Folk, and C&W seemed to be the exception that was largely populated by the singer/songwriter.

Then after Dylan, the media machine seemed to put importance on the fact that the pop artist should also be the songwriter.

Ironically modern country music (which I refer to as Nashville to differentiate it from "real" country) is now populated largely by professional songwriters and singers.

I'm not trying to make a point here, because I don't know what the significance of that is (if any). But just a passing observation on my part from my limited experience as a performer and an interested person and not a researcher.

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