Here's a quote from an interview Steve did over in England, where he indicates he wasn't too happy with John Denver's tinkerings with the song. (Though Steve is pretty well-mannered about it):

John Denver learned it from me in a hotel in New York where he was staying and he said "Steve, I really want to record this, but I don't think it is commercial the way it is and I want to re-write the last verse because I think I can say something with it." I said 'Go ahead' - I could have told him not to, so it's my fault. ... Still it was nice of John to even consider doing the song, but what I'm really happy about is that the version with the right lyrics is the one that caught on".