For me, 'mediation' per se is not necessarily a bad thing. Nor is it necessarily dishonest. For example, say you take an old song and put your own twist on it, say to reflect current events you happen to care about. Then this is a form of mediation. Interpreting and evaluating the opinions and attitudes underpinning that mediation is another matter, and one that can be done in many different ways. Even a person who made alterations might not remember exactly why they did it, or may not have done it with any great degree of conscious thought, or might later in life look back on it and interpret what they did in a particular way eg 'I must have been thinking about x or y when I did that version'.

I have no doubt that Sharp was partly motivated at various points by financial considerations. He had to make a living after all. The same to some extent with antiquarians who were interested in and sometimes dealt in manuscripts. Ditto broadside printers, and some of those who sold material to them. The same with a great many people who produced song books in the days before industrialisation brought in records, CDs etc.