Jim, I must disagree. "New" is a relative term, and above Gene admits that he sings "Sally Free and Easy" - which is not folk (although I do a version of it that is fairly heavily not "in the style of the tradition" so it is being adopted and modified).

I also do a version of "The ballad of Sammy's bar" in which I invert part of the melody.

Both songs are widely sung, and in their adoption they are changing (as is "Ride On"). The parts of the 1954 definition that are not met are that the transmission is often not by the oral process and that the composers are usually remembered - but for other songs that last part is sometimes met, too, for example "Fiddlers Green" and some MacColls.