Thanks for sharing that. I would suggest that there are many things that could go into selecting a tone for a particular piece of music, so swapping between basses may have just been a matter of what that bassist set up for that show. Flats on a jazz are popular these days, for example, and you'll get that thumpy tone from them. If the bassist wanted that thumpy, undefined stuff for some songs (ala Jamerson) then it makes sense that he might set up one of his basses to accommodate that. I would guess it wouldn't have to be the jazz, but as I said, flats on a jazz are very popular.