This is an interesting legal debate but the real issue is whether a licensee (or even a backing brewery) will want to involve themselves in this - I think they will take a "no risk" view and prevent music if they have no licence.

The rules of interpretation, as I understand them are that:- firstly the courts assume that Parliamnet is competent and interpret the clause literally. If this makes no sense then the mischief rule applies - what mischief did Parliament intend to prevent. If this fails there is something called the Goldern Rule but I fear I forget its meaning.(best possible explanation??)

The interpretation that the "incidental" acception means something is correct. What Literally does this mean. "to the extent that it is incidental to some other activity that is not a description of entertainment in Schedule 2" is interesting.   It therefore does not mean that music performed as a backdrop to a play is exempt because a play is described regulated entertainment. It must, literally, be music (recorded or live)incidental to some other licensed activeity other than regulated entertainment - so literally music incidental to (not a core part of) selling alcohol.

The courts look to Parliamnetary words but could be urged to take into account parliamentary debate. The wretched Howells, pressed to define "incidental" said he thought it was obvious but that he would have a shot at it. He waffled about a restaurant having a pianist playing in a corner...he thought that was ok (although the prime purpose of a restaurant, I would have thought, is not (as yet) licensed - ie selling food.

He said it would not be incidental if it was live music that was advertised and the main purpose of the public being there. So if a band is advertised to play at a pub and it plays loud enough - licence needed. if a session takes place undvertised and largely ignored by the regulars- no licence needed - incidental.

But these are fine points of law and not something I think even the most eloquent of us could pusudade our local licence to risk £20,000 &/or 6 months on.