Sorry about the late intervention - holiday (somebody has to do it!)
I can't think of a traditional singer we have met who didn't alter songs, often extensively; sometimes unconsciously, but mostly on purpose.
In Ireland, many of the songs were passed on via the ballad sheets which were sold at the fairs and markets well into the fifties. All of the singers we recorded learned songs from them and all of them we interviewed told us they used them as guides rather than set texts. Clare singer Tom Lenihan spoke at length about re-making songs he learned from 'the ballads' because he wasn't happy with the printed versions - he also did this with songs he got from other singers - listen to his 'Constant Farmer's Son' on 'Around The Hills of Clare' or 'Farmer Michael Hayes from 'Mount Callan Garland'.
Walter Pardon did it to a great extent - not, as has been suggested, to please potential audiences, but because he had strong opinions on how the poetry of the songs should sound. When he returned home after the war he began to write down his family's songs, particularly those of his Uncle, Billy Gee, who had died while Walter was in the army. His repertoire books make fascinating reading. He told us that quite often he could only remember a couple of verses to a song, but if he thought it good enough he re-constructed it, for his own satisfaction.
One of his best songs (IMO) was 'The Dark Arches', of which he sang the half verse and a chorus he could remember to us shortly after we first met him. He asked us could we find him a full text of it, and eventually Mike Yates came up with one from an old songbook. He then set about re-making the song by combining the fragment he remembered with the printed text - for me, comparing the two proved what a great artist Walter was.
Scots Traveller Duncan Williamson told us how he re-made many of the ballads in his repertoire from bits he gleaned from other Travellers.
I have always suspected that Jeannie Robertson did the same - compare her earlier recordings with the later ones.
One of my favourite bawdy songs is Arthur Woods' 'The Tailor's Britches' which, I have been told, he claimed to have composed, but which obviously came from an earlier text.
The older singers sang because they enjoyed the songs - not because they were in pursuit of 'authenticity' whatever that was.
Jim Carroll