"though it wouldn't be easy to sing along..."
I'm not sure what that means
What has always struck me about most of the emigration songs is that they are private expressions of grief, to be felt rather than 'performed'
To over-perform them can be to kill them
Even though I come from a family that first turned up in Britain as 'Famine Refugees', when we started collecting songs in Ireland and were given so many of these laments, I found myself thinking, 'Oh dear, not another one!'
That was until I realised their importance to the Irish as a people
Living in Ireland now, it's chastening to realise that I don't know a single family which has lost large number to emigration - and that has almost certainly been the case since the middle of the 19th century.
I think information like that is the secret to singing these songs - nothing to do with ornamentation or any other technique

For me, THIS is by far the most poignant song we ever came across on the subject
A daughter of the singer once described him singing this song at family gatherings each Christmas and reducing the entire room to floods of tears when they remembered how many relatives they had lost through emigration - it's not hard to understand why it had that effect   
Jim Carroll