http://www.lewisham.gov.uk/myservices/ed...wisham.pdf

At the back of this pdf are a set of tables that give the catchment areas.
Children were grouped into 5 bands and places were offered equally in each band.
If a child was grouped in 2A, then with a 2km range, I guess those se23ers NE of Honor Oak Pk station had a chance of being offered a place at Prendergast Hilly Fields. Otherwise unless the children were genuinely musically gifted, or had a special need, all in SE23 were most likely initially rejected.

Harris Crystal Palace's catchment area is 1m (90%), 2m (10%) so again SE23ers miss out there unless they pass the entrance test or have a special need. The test I believe is not dissimilar to the 11+ (with a technical flavour) and there are a ridiculous number that apply. They pick the cream so well done pebble!
Their results are superb, but they would be.

Places presumably come up in these schools for the very persistent, but they will be rare. It would be misleading to suggest otherwise.

On grammar schools, I do not think my door to door estimate of an hour is too far off the mark. Some children no doubt pass the 11+ without effort. Most will need to work on one or more parts of their skill-set. Primary schools are not 11+ prep schools. And my understanding is that passing the 11+ does not in itself guarantee a place at a grammar school. You need a good mark.

PS Does anyone know if Kingsdale's rather poor results are because of the BTECs they teach are no longer counting towards the 5 A-C (incl Eng and Maths) figures? I've not heard an explanation and I am curious.