"I feel that none of us is in a position to criticise the Coppers:"
Me too - I didn't think I was criticising them, certainly didn't intend to. I was just observing that the fact that their singing from a book, when they do it, produces a number of effects in their final output.
From what I have read and learned in discussion, their manner of performance is far more than 'just keeping the words tidy", but a long established family custom.
The only other singers who consistently produce a similar sound on all their songs are those revival performers who have set out to borow from their style.
"where in the folk club/singers 'rulebok'"
Who mentioned rules - I was under the impression that people were giving opinions, albeit strongly held ones.
Jim Carroll