mathsmum314 - Parents are more likely to send a child to the school that excels in the area their DC does, maths, technology, music, sport or whatever. If your child doesn't fit into any of these categories then they can go to any of them and still get a good comprehensive education.
I live in an area that fits this model i.e. selection is made by academic, music, sports, technology, sibling, cross sibling and distance.
Those children who have the most choice are those who are academically able, have very supportive families and are fairly well off.
Years 3 and 4 at school see a number of children moved to private preps. Other children spend much of their free time in music lessons/practicing or attending sports clubs/fixtures.
Distance cut offs for the schools range from 224 mtrs to 2 1/2 miles (houses closest to this school are outrageously priced and there are very few flats to rent). Opening up selection to numberous criteria creates a super selective area which sees those with SEN or financial constraints getting no choice at all.
To add to the problem is the many families who think these schools are more appealing due to their selectiveness so rent on the doorstep and move back to their family home once a place has been secured. This is leading to a shortage of school places in the area (even less choice for disadvantaged families).
A system like this will be a massive step in the wrong direction. Those already being disadvantaged will be significanly more disadvantaged.