Hamish Birchall
Case law, which forms part of Robin Allen's opinion, determines that between 1899 and 1961 two musicians (or possibly more) could regularly play a pub piano and sing for their own amusement, unpaid, and this was not regarded as a licensable public entertainment (Brearley v Morley, 1899). The Licensing Bill would, of course, render both the activity and the piano a criminal offence unless licensed.

The DCMS
This point is disingenuous. In 1899, the courts held that impromptu performances by customers were not licensable, but performances given by a customer or any musician "for a consideration" were licensable. The Report of the Royal Commission on Licensing (England and Wales) 1929 – 1931 (paragraph 249) confirmed this interpretation of the law. Working musicians were therefore not exempted as claimed. The "two in a bar rule" was introduced by the Licensing Act 1964.