Tired of London? Not exactly, but it is possible for those outside the capital to tire of hearing about it, its global fame, its glamour and its apparently unstoppable economic ­success. It sometimes seems as if Britain is in danger of being a rich megalopolis with a poor country attached, and that is not a promising development.  In Mind The Gap: London vs the Rest (3 March), Evan Davis wandered around the new, exciting and expensive bits of London, finding out how well the city is doing and asking why. The tone was set in the opening moments by the capital’s cheerleader, the mayor, Boris Johnson, who announced, with characteristic understatement, that “London is now basically evolving into the capital of the world”. Davis didn’t exactly concur, but he wa