Quick theory question about Whipping Post. Verses and solo is over progression A - Bm - C - Bm. The solo is played in A minor (seems mostly pentatonics and dorian). Is the idea similar to the general blues idea of forcing minor over a seventh chord? I guess I'm thrown off because the chords are only triads (not sevenths as is traditional in blues) and I'd like to think of it as ii - iii - IV - iii in G but that A is a major chord. Thanks for any insight.