blues guitarists are at their best when they're just flowing. i've seen so many guitarists try and describe this, but you have to experience it to really get it. it's almost a spiritual experience, as though your hands are being guided. it's some kind of trance. the music comes from somewhere else and flows through you. i'm as dour an atheist as you'll ever find, but this is something that happens; it may be largely psychological, or the result of releasing emotion, but the effect of feeling guided is as real as real can be.
you're consequently only really going to get this if you can feel it, the same way you feel a blues or fusion guitarist. it's entirely visceral. the arrangements are different, but the blues aren't about the arrangements. the blues are about the raw power. what an advocate of this will tell you is that it's visceral power is increased by stripping out anything remotely resembling conventional music. all that remains is the trance, and that amplifies it.
but, on some level, is he just fucking around on a broken guitar? well, yeah.