Bill Marwick's folk file; a wry look at this and other related subjects is worth a look.
The Folk File: a folkie's dictionary
folk process (see also oral tradition) the method of learning a song, forgetting some of it, adding bits of your own, and then teaching the song to someone else, complete with changes. This happens all the time, with the expected result that there are often no definitive versions of songs. Ancient publication doesn't mean much - if the song has been improved over the years, no one will go back to the authentic but inferior version, but still, the song retains its original form for centuries. john