...there’s a very good case for also allowing measures of two-thirds of a pint to be served, slightly bigger than the commonplace 330 ml bottles and almost exactly the same as the 12 US fluid ounces that is usual in America. It would have enough size advantage over a half to seem a more worthwhile drink, but be sufficiently smaller than a pint to leave you considerably more sober and less bloated. It would also be appealing to drinkers in multi-beer alehouses who want to sample a range of beers without ending up under the table.It would also (whisper it softly) allow the law-abiding driver to have three worthwhile glasses of beer rather than two.
But I suspect in practice it would lead to a notable drop-off in on-trade beer sales, so watch out for a lukewarm reception from trade bodies, who no doubt will whinge over the cost of acquiring new glassware. It would be interesting to know what proportion of pub customers simply drink one pint during their visit, and so thus would be prime candidates for downsizing.