Gibb,
An excellent summary of why this information is important. I was simply looking at it from my own limited perspectives.

Your perspective of why Lloyd's and MacColl's versions and contributions are important has a lot in common with why Child's anthology was so important. There is a heck of a lot of stuff in there that is suspect in one way or another and at times he pointed this out, but Child included all of it because even the suspect ones might contain a vestige of genuine oral tradition.