This is a tweet from Robert Coe:
"However, I think it is now fairly clear that selection increases segregation and decreases social mobility"
He is director of CEM.org, who conduct research into social mobility for the Sutton Trust. He is as expert and impartial as you can get.
Is no-one worried that the government is pursuing a policy in direct contravention of overwhelming evidence? It used to be that politicians at least pretended they were acting according to reason and evidence, whatever the reality might have been. To abandon even that pretence and act as if evidence doesn't matter is quite a dangerous step, I think.