It is a lovely song... I wish Archie played in the States more frequently. I did have the chance to see him at the Philly folk festival once, accompanied by the wonderously talented Garnet Rogers.
So if he plays it again, can you at least maybe notice if it's standard tuning or dadgad?
graci!
(and yeah, clinton, to my employer's chagrin I, ahem, spent a little time here yesterday afternoon...)