Just concurring with the views of Reg Hall, an early stalwart of the tradition- re- 'Lily of Laguna', the views I mentioned were expressed 50 years ago- if it's a good song, who cares if it is traditional or not- you lot can't even define it and PLEASE DON'T TRY!!!
Tell you what, given the choice of your two examples Brian, although I'd rather hear 'Lily of Laguna' sung well, I'd go for the drunk in the bar- the Child ballads are an important body of work but the chances of anyone giving a meaningful and sympathetic delivery of a Child ballad in 2015 are slim (at least 50 years ago there was a real possibility of hearing ballads in a social context)
There's always an exception of course delivered vibrantly to what is after all a tiny minority of the population- ie folkies)...
but such material is far better left to the academics these days I think.

It's maybe regrettable but that's the real world- 'folk music' is supposed to be for the folk after all- why do we put up these pointless barriers? -just off to the pub (where the folk spend time)- will probably do some Delia Murphy songs.
And in my experience, traditional singers never differentiated between these alleged 'genres' of music- they didn't know they were singing folk songs till song collector TOLD them & put all their songs in tidy little slots!