I am not a guitar player, but to me Furry Lewis’ technique seems unique. “Kassie Jones” is a song about a conductor, but doesn’t sound anything like the Grateful Dead song of the same — though differently spelled — name. It is quite possible that the later song was a tribute.
Wikipedia notes that Lewis was one of the first of the older African American blues players whose careers were given a second lease on life by the explosion of interest in their music in the 1960s
Smithsonian Folkways has a nice profile of Lewis. Here is the start:
Walter “Furry” Lewis (1893– 1981) personified the relaxed and intimate character of the early blues. A master of multiple guitar techniques, he was most notably an impressive bottleneck guitarist who echoed his vocal phrasings with an expressive set of sliding notes. He was able to give his performances a spontaneity, subtlety, and feeling that made him, in the words of blues historian Sam Charters, one of “only a handful of singers [of his era] with the creative ability to use the blues as an expression of personal emotion.” (Continue Reading…)