Hamshank, to each his/her own, of course, but to me "Grace"--as beautiful as it is--seems awfully slow and sad for a pub party. (I think it's even sadder than "Danny Boy," which, of course, is kind of a tradition over here in Amerikay.) I'd say the same about "Scorn Not His Simplicity" and some other beautiful but somber Irish songs.

Concerts (e.g., the Irish Tenors on PBS), of course, are a different matter.

I think the reason folks like to sing "The Unicorn," "The Wild Rover," and "Harrigan" over here on St. Patrick's is that they are lively and have choruses folks can easily sing along with.

In the pubs I've been in on St. Patrick's Day the music is mostly lively and upbeat, with a lot of emphasis on dance tunes.