Dick, my opinion, FWIW, is that there is a clear difference between the folk process on one hand and faulty transmission of misheard lyrics (Mondegreens) on the other.

I would agree that the example you quote is an example of the folk process at work. On the other hand, the line in Dougie MacLean's song "Caledonia", given in the DT as
"Travelled far, with coat-tails flying, somewhere in the wind"
is an example of misheard lyrics. A Mondegreen.

And there are, regrettably, many such in the DT. Perhaps if there were a Permathread on correcting lyrics, enough volunteers would be able to extirpate these errors .... I would certainly be willing to help, but I don't know how.

Murray