Well I'm sorry Jim - but thats the way it works. some kid turns up at the folk club singing Beatles song and ten years later - they're telling you about what constitutes real folk music and which Childe Ballads are which.

And actually when Nessum Dorma is being sung on the football terraces - well yes it has become a sort of folk melody - certainly one that folk musicians will have a crack at, write variants of = add words to.

Folk music doesn't follow any sort of pattern = folk define it. Not some arsehole with an agenda.