"I still lament the fact that most collectors never bothered to ask their informants what their songs meant to them,"

Whilst agreeing with this statement in principle, could I please ask the unfortunate phrase 'never bothered' to be rethought. What needs to be taken into account is that every time collectors went out to find songs they were of the opinion (not always correct) that these songs were about to disappear and therefore speed in getting down as many as possible was to them/us essential. The other aspect is that almost to a man/woman these collectors were private individuals with no financial backing and no formal training. That was until the 1970s the situation, not ideal, but if these amateurs hadn't become interested we would have precious little left today.

The fact that Jim was able to do this is greatly to his credit, but please don't castigate those who didn't because their priorities were slightly different. Most of them had paid jobs and families to look after and their time was limited.