I don't think that you have quite understood Blandiver's point, Dick. He was trying to distinguish between the songs that have emerged from the tradition (which he would call authentic) and the modern songs that have been written by folk singers for a folk club/singaround audience (which he would call pastiches).

For people like Blandiver (and for myself, actually) the distinction is important - and clearly he wants to keep the two separate.

On the other hand, you make an important point when you say "the only thing that makes me decide to do a song is the merit of the song not what category it fits in to". There is some drivel that has emerged from the tradition and some modern songwriters who are inspired by the tradition have composed some superb songs. I would give Dave Goulder as my example of the best of these.

Of course, new songs must be written; we cannot allow our movement to ossify, but when I hear songs that sound as though they have been written with the market in mind - whether it be for a folk music audience or for a broader music industry audience I, for one, find it a real turn off.

As for quoting a short piece from a traditional song in a modern composition, I think that many people would regard this as a tribute rather than plagiarism.