John, you make some very good points, but they seem to contradict your opening premise -- that singer/songwriter music (however you're choosing to define that) is antithetical to folk music. I agree with you that "traditions" (another loosely-defined term) can arise in a relatively short period of time, as has happened with citterns in Irish music. I think this is particularly true in the modern era, when the pace of everything has been speeded up. But if that's the case, why should we exclude the singer/songwriter "tradition," which extends back through Dylan to Woody Guthrie, Blind Blake, Robert Johnson, etc.?

You may mean that you just don't care for the image of the "singer-songwriter" that you carry in your head; young, angst-ridden post-adolescents who try to appear deeper than they really are while singing obscure and unmemorable self-penned tunes. I might agree with you about that, but I don't think that the whole genre should be excluded from the definition based on personal preferences and stereotypes.

Much of the singer-songwriter genre arose out of a true folk process involving musicians learning from each other, stealing from each other, altering words and melodies to suit their personal vision, whether or not there was a commercial component or incentive. I am part of that tradition, and I don't see a marked difference between it and similar processes that might have arisen in different times and locations (18th-20th century Appalichia, early 20th century Mississippi delta, etc.) that are more generally recognized to be part of the "folk" universe.

It's an old debate on this forum, and I'm anticipating groans as I write this. But for all that has been said on this topic, I have yet to hear a persuasive argument (IMHO) against what I'm suggesting.