Very few people, even in Scotland, would be able to figure out the chorus of Twa Recruiting Sergeants by ear before the song finishes. They'll need it on paper.

The chorus is not too bad, I don't think. I managed to get it orally after about two or three playings through and I last lived in Scotland in 1965. The verses are a different matter. I needed to go to paper for those and to check on the dialect words.

"Jock O' Hazeldene," but you'll need a good range to do it justice.

I don't have a large range and I can manage it quite comfortably. The important thing you need to realise is that it starts on the highest note in the tune, so you need to be careful not to pitch it too low.