Shambles makes what seems to me a decusively good point. If the Dudley rules are an accurate statement of the situation - and Richard Bridge said he reckons they are - then clearly sessions where no charge is made in advance are not "public entertainments" -

"The common definition of a public entertainment is one which involves one or more of the above activities, is publicly advertised and where a fee is charged either before the event or on entry."

Of course it then goes on to talk about places with liquor licences being allowed to have two performers, and no dancers, under their liquor licence - but if that first definition is accurate, that would only be relevant to the situation where the place with a liquor licence is charging admission - as pubs often do on special occasions, such as New Years Eve.

So maybe we've all been labouring under a misunderstanding all along, and pubs do not in fact need PELs for sessions - and they don't even need to worry if a few people start dancing sets, as does sometimes happen in a good Irish session.

Clearly it would be useful to have a link to the actual legal basis for all this, the relevant Act etc, which I imagine should be available online. So if some clever person could hunt it out and blue clicky it...