Time for a more rational debate on 'mixing' in new developments?

[Posted by Prof Henry G. Overman] I may have made this point before, but I would love to see more sensible discussion of policy around mixed housing developments. I was reminded of this by the Guardian headline on Saturday about 'Poor doors' which highlighted the segregation that goes on in some of these developments. Personally, I find such stories unpleasant, but not at all surprising. If you share that sentiment surpress, for a moment, your outrage and ask yourself the following question - if the uncomfortable truth is that wealthy people don't want to mix with their poor neighbours (and can't be forced to do so) then what, exactly does this policy achieve