In my entry on FOLKLORE in The Continuum Encyclopedia of British Literature [NY 2003], I wrote "Many singers steeped in tradtional song , such as Ewan MacColl, Cyril Tawney, Peter Bellamy, Bob Pegg, Peter Coe, succeeded in creating new songs in the traditional idiom that the revival had brought to a wider audience" [italics added]. The essential point is that these original songs were made by those within the folksong movement, who went on simultaneously performing within it as well as introducing some songs of their own. The same applied to others mentioned above {McGinn, Jansch, Bryant, Pickford, Seeger...}. Their songs were not pop-infiltrators, but made by those who understood what a folksong typically was and what it typically did, and, I reiterate, went on singing them alongside their original contributions. That surely is where the line requested above by Will Fly et al will be drawn.