Glad to see this old thread resurrected, especially in such an interesting fashion by the "OP" (original poster).

When I first heard this song played by the Dead, the chord progression sounded familiar, pretty much the way I had heard it played acoustically by folkie-types, in person and maybe on records.

Allowing for transposition from one key to another, I've always considered this song as one that always uses (in essence, that defines) a certain characteristic chord-progression that is quite distinct from the standard 12-bar-blues routine ~ even though the verses are three lines in length, same as a standard blues song.

When I learned from this thread that Bob Coltman is apparently responsible for this standard/popular version of "Know You Rider," I began to consider his accomplishment as very similar to Dave Van Ronk's resetting of the traditional "House of the Rising Sun" to an innovative set of chords, the arrangement made relatively famous by Bob Dylan and then, later, world-famous by the Animals...