The principal current topic among political commentators, whether in broadsheets or in the bar of the Dog and Duck, is whether there really has been a political revolution in Britain or just a fluke election result unlikely to be repeated. In more specific terms, are the Conservatives just the chance beneficiaries of the perfect storm (Corbyn/Brexit) that engulfed Labour at the election and will northern voters return to The Party We Used to Love at the next contest, or does Boris Johnson have a realistic prospect of retaining their support?