Back in about 1970 people grumbleed about Ewan MacColl's alias because he was so high profile about authenticity - you could sing only songs from your "own tradition" in his Singers' Club - and he was very scathing about anyone who made a "performance" of a folk song, so the assumed name thing rang a bit false. I don't recall anyone ever explaining that in his case it was a legitimate Equity requirement - probably none of the folkies ever knew. Maybe Karl Dallas could comment?

SJ