OL. "We must remember that deep within our music is a national identity"

Ballocks. Absolute crap. The traditional musics of these isles were formed and made by those people who used to be demeaningly described as the lower orders. If there is any sort of identity in traditional music/song at all it is a communal/class identity.

In any event, apart from the fact that the English, Scots and Irish traditions have been swirling around for so long that it's hard to know where one begins and another leaves off, what sort of influence does OL imagine the music of continental Europe exerted on "our native" traditions? Dunno. Can't tell you. All I do know is that whenever I listen to European traditional music I can hear all kinds of echoes of music from neare home.

You've fallen for the same mistake that Sharp made a century ago and which Griffin and his acolytes continue to make today. IE., they suppose that national social culture is something fixed and immutable and buried in our genes and somehow sewn into our folk music. It isn't. All aspects of our social culture, music included, are in a continual state of flux, and subject to external influences, and have been ever since different groups of people learned to interact with each other.