It wasn't until I was past this spot that I realised something had gone wrong - the bloke getting out of the car at the corner with a notepad in his hand was clearly about to exchange details with the cyclist. The cyclist was in pain, and as I looked back, I could see that his front wheel was quite bent up.
I was pretty sure that having a 3rd person standing at a bottleneck would do little good, especially as the cyclist was standing up and breathing, so I kept on going. Gawd knows what happened - the cyclist might have tried to cross on the red, only to find that cars coming from the left had a green arrow, resulting in splat. I don't know - this is all speculation.