Rudely, A couple of hours is a bit much for any performer and I can think of very few who would accept such a booking. But a couple of 45 min spots is no problem. I have been a Folkie for 55 years and have run Clubs and Singarounds for around 30 of them, given help to many, lent Concertinas to quite a few and started several Singers off with some books to start their library. Being "rude" is not productive like a great many I am dismayed at the falling standard of some Singers who just seem to not care about the Tradition and the Heritage that is in their material.
Jack, you are right the Cellar is a lovely Club, great Singers and a love of the material. Only problem for us is that the last train leaves St Pancras at 10. 30