Okay Shimrod, I'll give you one parting shot to suck on. Where in the sainted folk process is origination, not transformation and the magic folk dust that scatters, but the thing those songs were based on?
Did the words aggregate one by one with the each person adding another like a radio panel game, or did someone work out the verses? Which of those is most likely?

Praise the tweakers, but respect the unknown word warriors. Tara!