As a singer I'd like to comment on the textual change: "door step" becoming "stepstone."

In some locales, "stepstone" is probably the correct term in use. But strictly as a singer, I can say that "stepstone" sings much, much better (at least to the tune I know). If it originated as "door step," I'm grateful that the folk process changed it, because if I had heard it sing first as "door step," I do not think I could have imagined singing it, myself. As a line in a poem, it works handsomely; as a song-- to the tune I know-- it doesn't at all. The vowels for "stepstone" fit the tune, and the snapping of the consonants fits the rhythm.

~Susan