The problem with that is that Bert Lloyd had (and cultivated) a considerable reputation as a serious scholar; as a result, people took it on trust that material he came up with was genuinely traditional.

Frequently this wasn't the case. There is a big difference between the 'folk process' changes (if we have to use that much abused, and much misunderstood, term) made by singers from within a living tradition, and what are essentially 'editorial' alterations made by people from outside it. Bert's interventions, although they were usually eminently successful from an artistic point of view, and informed by a genuine and extensive knowledge of traditional idiom, were nevertheless often just as bogus as the regularly decried editorial changes made by earlier collectors like Sharp and Baring-Gould.

Lloyd arrogated to himself the privileges of the traditional singer while expecting also those of the academic scholar. The two are rarely compatible, as the former is expected to introduce variation while the latter is expected to be scrupulously honest about his or her sources and to present them exactly as found; or, failing that, to be specific about any editorial interventions.

It appears that Lloyd wasn't above inventing a fictional 'source' in order to pretend that one of his re-castings of a song was a genuine product of oral tradition. His version of 'Reynardine' is a case in point; and it may not be irrelevant that, when a mutual friend of Dave's and mine made enquiries at PRS about publishing a recorded arrangement of that song, Lloyd's name was on the copyright file.

Of course, none of this 'matters' to people who just want raw (and out of copyright) material; people who want to understand where a song has been, and what has happened to it along the way, have a very different attitude. That's what [Jonathan] Lighter (who has pretty impressive academic credentials, and isn't asking an idle question) means here, I think.