quote : - "I have a century old tried and tested identification of folk song"
.... but it is far from being the only one so please allow other people's view of the definition to stand. Many modern scholars from A.L.Lloyd and Hamish Henderson onwards have shunned a precise definition of 'folk song' as being of little value because of the wide variation in the usage of the term. You would give more credence to your statements if you sometimes used qualifiers like "In my opinion...." or "My experience leads me to believe....." rather than making bald statements as if they were factual when they are not.