"is it OK, is it OK if you state what you're doing and don't pass it off as the original thing, or is it completely beyond the pale."

Every singer will have a slightly different interpretation of these songs; every musician will arrange them differently. Even

Maryrrf, the "fuck 'em" was I think a perfectly valid response to the dreary and ahistorical bullshit approach to folksong that appears to have been adopted by this club. One, we can't possibly kow how thesesongs sounded when they were first written and two Fred Jordan doesn't sound like Nic Jones doesn't sound like Mawkin Causley. The interpretation and presentation of traditional music is not and can never be static. Those who would seek to impose stasis are not doing the music any favours.

A few people may like that misplacedly rigid approach - bully for them. Their loss.