Good point Pavane. Lots of us have used the term "scholarly" because it covers most kinds of academic study.

The treatment of evidence and hypothesis building is generally the same for science as it is for history, economics or philosophy. The exceptions are probably creative arts and religion.

Bert knew about evidence that's why he was so good at making it up to support the hypotheses his Marxist background had helped him to generate. He had decided that the industrial working class were part of an oral tradition akin to that of the rural working class and so he doctored songs and in some cases made up sources to support that hypothesis.

Their are lots if "Industrial"songs but I suspect most cold be tracked back to their authors. Many were recorded in only one variant and so had not been molded by an oral process as were many rural songs. This in no way detracts from their value either as songs or as social records but it does make them different.

Cheers

Les