I don't think we can entirely escape the 1954 statement, ESPECIALLY   the existence-of-variant-versions requirement. It is something that non-folkies don't understand — I once many years ago played my father the Copper Family's Presents Song - ie their version of The 12 Days Of Xmas, & he was genuinely distressed and disorientated: "But that is an absolutely standard song that everybody knows" he kept saying. Whereas we all know about versions, the oral tradition, and so on; and it is to a huge extent the existence of variants that bespeaks to us the true traditionality of a song, tale, dance, &c, however any particular individual might perform or choose to accompany it and in whatever style.