Warning: thread creep

Walkabouts Verse quoted: "If folkies must test their technique by improvising on/"doing something with" a traditional tune, then, in my opinion, they should begin their performance with a run-through of just the top-line melody – otherwise, there would be no oral-tradition of tunes!"

More twaddle, unless the writer is discussing folkies stretching tunes as radically as is done in jazz, or singing them flattened out in rock style. Improvisation in the trad singing world refers more to the variation of the common elements of the tune, which may be done either subtly or more noticeably. It is not necessarily pitch-focused (like melodic variation in sean nos); in English trad singing, timing variations are often more pronounced.

A "tune" is just a concensus of the musical elements most common to the many renderings of it; it's an abstract pattern. Audiences quite astutely pick up on common elements in recurring passages, so that by the end of a song they will have formed a mental model of "the tune" even if it has never once been performed in that basic form. The oral tradition has little to fear from this sort of improvisation--it's been going on for centuries.