Trying to get back to what I think Al's question to be - I find 'The Prickly Bush' and 'Hunting the Wren' to be songs that go on far too long, primarily because of the repetition ("I think I see my third cousin twice removed on my mother's side coming" ...) but I know plenty of people who think it a great song. On the other hand there are some ballads that are ten to fifteen minutes long which I really like that still have a fair bit of repetition in them ("You shall [do something]" ... "So he [did that something]"). I think the problem is that the songs I don't like are almost all repetition, unlike the ballads where it is more like an emphasis of a part of a quite complex story.