Now I realize that my language was probably unclear. The "new (and in this case, better) song" I referred to was Jefferson's composition. The "original song" I referred to was Gus William's parlor song. To rephrase (one last time, hopefully): If the 1876 song was Jefferson's source for "One Kind Favor", the relationship between the two illustrates how the folk process and the genius of individual performers can improve upon non-folk material.