Joan was quite proud of her bare feet, which were said to be very attractive ones by various people at the time, and she walked around barefoot a lot and often performed that way too. I guess that's why they got dirty, eh? ;-) There's even a live recording from the early days where she asks the audience at Carnegie Hall if it's okay if she takes off her shoes...and gets some enthusiastic applause. Some wag should have yelled "More!", but no one did. They were very well behaved in those days at folk concerts.

As for the riff...hmmm...sounds neat. I'll see if I can figure that out tomorrow.