All true Whistle Stop.

But more, the process of passing on and adding and removing bits, one of the best bits of the oral tradition, is how we end up with 'folk songs' as opposed to simply 'old songs' isn't it?

As has been expressed in other threads, not least by Malcolm Douglass, he of the RVWML, I think, old songs are a lot more common than folk songs but that oral tradition is a fascinating process.

I think Bob Peg pointed out, in a book I could go and find, guitar bands learn most of their songs via the oral proces. What ever we might say Beatles songs are passing into the oral tradition as we tap and mouse!