Lis - sometimes a session needs an 'organiser' so that everybody gets to sing.   Some individuals/groups are greedy and just carry on singing other songs, and don't let anyone else in.

The trick is solving the problem of individuals/groups being greedy/inconsiderate and all the other problems listed here, without losing the freedom that make these events so good when they work.

The 'organiser' concept, especially in a pub, is not a solution. In fact I think that it can cause folk to be even worse.

The benevelolent dictator idea, usually self appointed, is one I have difficulty with. No matter how fair this 'organiser' of more accurately 'leader' is trying to be, there will be some folk who feel that they have not been given as much time as other more favoured folk etc, and probably with some justification.

The reaction is usually to 'milk' the precious spot that they are given, to the detrement of everyone.