Steve, I still don't get where you have evidence that supports so dogmatic a stance. Why can't existing songs have been fixed in print for commercial reasons? If such material was orally generated then there would be no previous printed version. I know you want to believe but there's still too much of a leap of faith required.

In support of Jim's comment by the way. I have had similar experiences at school during the 60s. As a secondary school teacher myself I find it unacceptable but it was a fact of life for many in earlier times. But…I had a brilliant English teacher appeared in 1967 who taught us in the 6th form about Marvell, Owen, and poetry in general. At a technical school this was heady stuff and his influence alone offset much of the other type of comment. It was this guy who's called Roger Elkin by the way who got me into writing poetry and subsequently songs. One positive overturns any number of negatives in my experience.
Paul