With multitrack capability, they were recording instruments first and then adding vocals. This gave John the chance to perfect the banjo part in the studio. His playing is very distinctive. Other than the Reverend Mr. Black and Desert Pete (as Rick noted by Glen Campbell), I never noticed any other tunes that weren't in the "Stewart Style."
Just curious about John's banjo work. Possibly a ringer was brought in for some of the studio stuff?
I admit that I feel that the KT's best work was done at Capitol, and that I also am drawn more to the Guard years than the Stewart years. However, I was listening to #16 recently and was reminded again how much I like Erie Canal and particularly John's brief banjo riff. For all the talk about not being "folk singers," they sure do a great job on this one.