Just tried to read throuigh this whole thread at one sitting. Make it to about the halfway point before I started skimming. A few random reactions:

"Novosoto [TX] is not in the Piedmont." Well, neither is Avalon MS, but Mance Lipscomb and John Hurt were both exponents of the "Piedmont" approach to fingerpicking and song selection. It is very probable, statistically, that both men's forebearers spend a generation or two or more living in or near the Piedmont area (foothills of the Appalachians, in Virginia and the Carolinas) before being sold and shipped west to the newly-opened territories of Mississippi and Texas.

I find that there are indeed plenty of British white guys who can express themselves effectively as blues singers (many, but not all, in the popular electric-blues/rock business). The problem, of course, is to strike a balance between self-expression in one's own voice versus preserving the right bit of adherence to traditional diction, vowel-and-consonant soundings, etc. One doesn't want to slavishly imitate an original artist who inhabited a world and tradition vastly different from one's own...but on the other hand, it won't sound at all like The Blues if the singer does not adopt certain linguistic conventions which are as much a part of this traditional "sound" as are the chord progressions, the flatted fifths, and other strictly musical elements.

I had the good fortune of meeting Mance when I was a college sutdent, back in about 1968. Most vivid memory: Mance pulled out his false teeth (upper full plate) to show me the mother-of-pearl inlay picture of a guitar that he kept on the roof of his mouth all day every day. I think his first name was also part of the design, but my memory is less clear on that score; I can still clearly picture the little picture of a guitar. I think he said that the inlay was done for him, as a gift, by a fan who worked as a luthier...