Having run Ballad sessions for various festivals over the years I decided to find out what was sung and how often. Over a week of Ballad sessions at Whitby Folk week in 2009 there were an average of 20 songs per day. The longest, despite the perception of this material, was Cuthbert Noble's version of 'Tam Lin' at 9'20". The average length of song was around 4'50". The strangest thing to me at any rate was that Child 200, 'The Gypsy Laddie', never saw the light of day either that year nor the previous year. Two versions of 'The Bitter Withy' were identical but for the inclusion, or the lack of, the verse with the line, 'I'll make you believe in your latter day, I'm an angel above you all'. The choice of making the Christ child culpable in the death of the lords' sons left to the singers.
I learned Child 200 (admittedly a bit dubious on the tune front) from my father. I've collected 'Lord Randall' from a twelve year old girl at work and 'The Lovers Tasks' is so common in East Yorkshire as to be unremarkable. Maybe that's the point, some of these songs are just childhood ditties which we, folkies or academic folkies, choose to elevate to a status which perhaps they don't warrant? Living tradition? course it is, unless you want to muddy the water with 'folk revival' baggage.