Let's not get carried away (even by fairies)! This is very much a "drawing room ballad", to be sung with hands clutched across your stomach. The bits of Gaelic are, I'm afraid, an affectation - rather than something growing out of the song or out of an existing tradition.
All that doesn't take away from a beautiful tune. But as a song....?
Regards.
p.s. I'm well aware that songs of this type can sometimes be transformed into magic. I recall "The Shortcut to the Rosses" being sung once in a way that made the hair on my neck stand up - but I also recall hearing it sung hundreds of times in a way that made me cringe!
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