Jim, much as I hate to say this, you are just holding hoops up and the more I jump, the higher you hold them. I am not jumping any more. I have applied your criteria to a song that I put forward as being in the folk idiom and it passed every single test. You are trying to get round that by applying further tests. IE it must sound like something else. Sorry, but I have followed your rules and proved that a song written by someone you do not like is indeed in the folk idiom.