About 8pm tonight, A3 (West Hill; Putney-ish), riding a black Monster with a yellow frame. Not only was he riding a bit too aggressively in that heavy London-bound traffic, forcing cars to give him way, but when it got a bit too stationary for his liking (I was still moving, though, so perhaps he should learn to filter better), he decided to mount the pavement and ride there for about 100 meters before joining the road again, on the cycle lane. And he wasn't going slowly, either.
I somehow felt that the overriding bike related memory the witnesses have from today is not me giving a friendly wave or a nod to say 'thanks' for giving me way, but this hooligan behaving badly.
With all his stupid riding he shaved all of a minute or so from his lap time. Wow.