See Stephen Law's blog – Ban private schools? – the freedom issue. Is the topic addressing the underlying question?
It may be desirable that the possession of native wit should not be disadvantaged by school, or even by family. Does this mean that native wit should be positively advantaged – positive discrimination? Should the "better" (assuming greater native wit is better than lesser native wit) always be promoted above the "lesser" in order to achieve "equality"? Equality of what?
1) Make a consistent high quality education suddenly available to all (no resource or access problems). Those with higher native wit would be advantaged, since they'd make better use of it. So we need to address this imbalance, in rule 2.
2) Introduce corrective brain surgery to bring the lesser up to scratch with the better. Surely the "better" should have access to the same corrective surgery to improve their capabilities, so maintaining an imbalance. Well, we don't have corrective surgery, so instead let's just boost the education provided to the "lesser" – oops! Denial of service to the "better" and the breaking of rule 1.
Which is required, equal access to a service that improves your capabilities or equality of capabilities? This appears to be the basic question here.