An article in the Daily Telegraph
shows that the most exclusive comprehensives take in a smaller percentage of poor pupils than grammar schools with some admitting less than 10%.
Property prices as well as academic selection are determining entry to some secondary schools as certain wealthy parents move into areas where their children either take the 11+ (having been given the tuition opportunities to maximise their entry chances into these schools) for grammar school entry or they buy property in the catchment area of these high ranking comprehensives creating an apartheid not just within the state sector but the comprehensive system.
One answer to counter the distortions in the housing and state school market is to set up free schools at considerable taxpayers expense to increase choice although the pupil demographic profile could come under scrutiny as middle class parents move into the catchment area of these particular schools compounding the existing problems.
The other more altruistic solution is for middle class parents (like some on here) is not to move house or suddenly find God, but to support their local school and raise standards from within so that as the bar is raised other parents won't feel an obligation to move into affluent localities. This will have the benefit of giving more balanced intakes in schools.
Speaking personally, I'm sure my children's academic outcomes wouldn't have been improved by choosing a private school or an elite comprehensive school because I don't think the standard of teaching would have been any better than at the "below-average" comp they attended. But rather than leave their education as a matter entirely for the school I supplemented their teaching by taking a personal interest so the kids had maximised their potential when they took their GCSEs (and to a lesser extent A'levels).
I'm sure this is the route to go to help arrest the divergences in the comprehensive set-up.