Nice thread Dread.
I read what Armstrong and Bechet were talking about in rag-v-jazz-v-blues as "(re)packaging." It's been the standard process in American entertainment for centuries. Everybody, and I mean everybody, from John Durang & John Bill Ricketts to Mitch Miller did it.
So, at the risk of drifting back on topic... one more chimp who isn't here... Moe Asche. In packaging terms the "Sad Bluesman" is descendant of the abolitionist's "Sad Mulatto" and minstrelsy's "Sad Darkie."
The history of the "blue note" may go back centuries. But American variety artist and audience awareness of history will be limited to a few decades at best (as Lomax observed, liking it or not.)