"Most of the people round here who sing their songs learnt them directly, not from books or recordings."

Perhaps the reason for that is a matter of access. When Cecil Sharp and other collectors were doing their work at the turn of the 20th century (and even later), they were working in rural areas of this country in many cases. The public library system that we currently enjoy was not in place in many areas. Access to books was limited. Printed sheet music was slowly coming into vogue, and recordings were very rare. My mother grew up in Pennsylvania, and she remembers being one of the first families to own a radio and how the neighbors would gather to listen - and she lived about an hours drive from Pittsburgh.

Is it fair to NOT consider modern technology? IF the phonograph was invented 50 years earlier, perhaps collectors would have been "tainted"?

My mother used to sing alot when I was a kid. I learned the song "Mairsey Doats" from her, not realizing until my adult years that this was a song she learned from the Big Band era.    If I sang that song to a collector, would I not have learned it from the "oral tradition" - flavored by whatever changes were made?

I mention this because no one responded to an earlier question that I posed - why would it be so important to hear a recording of a Child Ballad that has already been published and not a Music Hall song that may have gone through processing to evolve into a unique song?