Hi DavidSpaven - thanks for inspiring me to think/write about rule 170 in the first place (although I'm pretty sure that wingpig has educated us on here about it before).
As I think someone said, as a cyclist, it can be quite risky to stop for a pedestrian in this sort of situation if there's a car behind you. because nine times out of ten, the car won't be expecting you to stop. So, I stop when it's safe i.e. when there's no car behind me, but some other times I will slow/go around.
I have, however, taken to stopping and explaining to pedestrians who try to wave me on, by saying 'No, you have priority, it's in the Highway code'. Needless to say, they all think I'm crazy.