“Take back control of our borders” – that was the aspiration voiced at the last election by pro-Brexit Conservative politicians. So, how is that going? Pretty well, one might assume, since the Tories won and got Brexit done. That, however, would be a false assumption, as has just been revealed by the Migration Observatory at the University of Oxford. It transpires that the data on immigration since 2012 has been hopelessly inaccurate.