BLJ may have been as old as 50 when he died(Some people have placed his birth around 1880--

It had always occurred to me that each of his tunes had that well worked quality that only comes from time--he seemed to be able to pull any number of arrangements and even sets of lyrics out for any given tune--meaning to me that he knew the possibilities of each of the positions that he used, inside and out, and that he had long ago dispensed with the basic form of a tune, and had re-arranged it, and each number was exactly like he wanted it-even going so far as to moving the chord change, or dropping the chord to create tension--

I don't have Black Snake Moan on CD (my turntable hasn't worked for a while), so I can't speculate on what is there, but you can often get a leg up on his C position turnarounds if you play the C bass note on the low E String with your pinky, and ride down to the A, pop in a D note or D-F#-C triad, and grab G note and/or chord before hitting the open C chord--

He layed out the palate for every jazz, blues, and rock guitarist that followed--and many of them built careers on just one or two of the devices that he used--

You don't need to work out everything he did--in fact, you can keep yourself busy(and happy) for a long time working with just a few of his licks--