Greg.
I mean the songs have entered the tradition,that means[to me] they are songs about fishing being sung by fishermen,the Birdie song and ooh bla da,are not songs about the singers occupation,
The Durham Lockout[Composed piece]is considered to have entered the tradition for the same reason,
Which songs has Dylan ever recorded/performed that are composed by other people,I cant think of any,In fact most songwriters very rarely perform other peoples songs.
In the following book The Shuttle and the Cage there are composed pieces including the Gresford Disaster[which has entered the tradition].
here is the preface from the Shuttle and The Cage[Ewan Maccoll march 1954]
There are no nightingales in these songs, no flowers - and the sun is rarely mentioned, their themes are work, poverty, hunger and exploitation. They should be sung to the accompaniment of pneumatic drills and swinging hammers, they should be bawled above the hum of turbines and the clatter of looms for they are songs of toil, anthems of the industrial age.

Few of these songs have ever appeared in print before, for they were not made with the eye to quick sales - or to catch the song-plugger's ear but to relieve the intolerable daily grind.

If you have spent your life striving desperately to make ends meet; if you have worked yourself to a standstill and still been unable to feed the kids properly, then you will know why these songs were made. It you have worked in a hot pit, wearing nothing but your boots and felt that the air you were breathing was liquid fire, then you will know why these songs were made. If you have crouched day after day in a twelve-inch seam of coal with four inches of water in it, and hacked with a small pick until every muscle in your body shrieked in protest - then you will know why these songs were made.

The folklore of the industrial worker is still a largely unexplored field and this collection represents no more than a mere scratching at the surface. A comprehensive survey of our industrial folk-song requires the full collaboration of the Trade Union movement. Such a survey would, undoubtedly, enrich our traditional music.
Fiddlers Green and Three Score and Ten have entered the tradition,[imo]because the community that the song is about,has taken the song to its heart[often regarding it a traditional]and sings it, because that community through its work experience relates to it.
Jim nobody through their work experience relates to the Birdie song.

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