Yes thanks jollyrog, some useful ideas there.
I used to drive this way every morning and I knew that if I was there before about 8.10am I would have a clear run past St Dunstan's (going east).
Five minutes later and I would be in a queue of what we once called "Chelsea tractors", really big wide beasts, with one tiny child on the back seat and I just knew I would be very late for work.
With the vast green spaces that St D's has, I am surprised that their parents haven't demanded a better drop-off route, with an entrance and exit away from the Catford Chaos junction.
Definitely worth talking to TfL: the whole area needs a proper survey as I'm sure there are a few simple solutions like moving bus stops.

If money was no object then a whopping great bypass bridge is what's really needed.