Jean Richie gave a wonderful interview to The Irish Times some years ago; her comments on using 'Barbara Allen' to draw out the traditional songs from field singers should be compulsory reading for anybody interested in the subject.
The term 'ballad' is used by older people here in Ireland to refer to the song sheets sold around the fairs and markets up to the middle of the 20th century.
As far as the tradition is concerned, the Famous Three-Hundred-And Five' is as good a starting point as anywhere for debating the ballads.
Jim Carroll