I'd add one other thought here, on the value of tradition. There is no question, at this point, that I like pedantically nitpicky research because I'm a pedentically nitpicky person. :-p

But why did I choose to be pedantically nitpicky about traditional songs (and textual criticism, and other specific areas), as opposed to the other autistics whose special interests are dinosaurs or Star Wars or models of refrigerator compressors? Because traditional songs tell us something. The earliest ones give us a certain insight into the way non-gentry people thought at a time when only the upper classes could write down their feelings.

Newer traditional songs aren't out only insight into the feelings of the common people, but they are still a source of insight. If there are two songs that participating soldiers wrote about (say) the Battle of the Bulge, and one goes into tradition and the other doesn't, that presumably says something about the traditional song and the story it told. What? That doubtless depends on the song and many other things. But the mere fact that it has become traditional is a piece of information that I did not otherwise have about the song.