The only way to challenge a planning decision (for an objector that is) is throught the high court. A recent decision is of interest:

http://heathandhampsteadsociety.org.uk/i...&Itemid=34

This was through the local civic society - is there a role here for the various ones in SE23? Or should an individual be prepared to stump up ?10k + at the risk of losing far more.

Of course the well funded developer can continue to apply, and had the option to appeal decisions, so one could summise would eventually get their own way (or of course get fed up with the process and hopefully move their attention elsehwhere).