The other jazz influence, IMHO, comes from Dixieland jazz in that each instrument became a lead instrument that played around the main theme, defining it by outlining it rather than playing it directly. Add to that substantial improvisation, and throwing in significant portions of blues, R&B, country, folk, good ol' rock 'n roll, and Americana, and they created a completely original musical recipe. This at a time when most other rock music consisted of a rhythm section with the lead guitar wailing.
Bill, tgo