The finer subtleties are lost on me but according to those that understand these things he is playing the lead and the base at the same time on the same 6 string guitar, funny thing is that a lot of them were not literate and listening to some of the interviews were very modest and yet had huge amounts of talent. I really admire their love of what they did.
Another great Muddy waters was a car factory worker 6 days a week and used to play gigs in peoples houses on the weekends. In an interview he said something like, you don't just get up and walk the streets and play the blues, you gotto suffer!
Try telling that to twat factor.....
Another Legend:
http://www.youtube.com/watch?v=8hEYwk0bypY