Dick wrote: -
Scan Tester played EDELWEISS, so what
What is interesting is not the fact that Scan played "Edelweiss" or "Puppet On A String" but the changes that his playing on a C/G anglo-concertina brought by his interpretation. Scan could see the potential for those tunes and they went through the process that Scan's playing brought to them. He played the keyed bugle in a militia marching band as a young msn and some of these tunes he returned to as dance polkas later in his life.
It is what happens; traditional musicians hear a tune from another genre and realise that they can consciously or consciously adapt them for their own purposes.
How many hornpipes came into the wider English repertoire from the entr'acte tunes of clog dancers with travelling theatre companies?
Why did so many Tex-Mex musicians become entranced with "The Birdy Song"?
What made the magnificent Malian balafon player, Kélétigui Diabaté, realise that he could bring something new and exciting to George Gershwin's "Summertime" to make it sound like an old Manding classic?
A Finnish waltz whose title in translation is something like "A Walk in the Woods" was taken across the Atlantic, words were put to it and several top artists recorded it in the 1950s as "Mocking Bird Hill". It came back across and was taken up as a waltz with variations in the north of Ireland.
It is what happens. The tradition becomes richer for it. We should celebrate it.

Sorry if this takes us off topic. I have just renewed my EFDSS subscription this week but if I see the organisation continue to move from being a grassroots organisation to being part of the Arts msinsteam mainly benefitting professional exponents (and I see the proposed change of name as part of this process) then I think that shall not be renewing next year.