I think this post is a really interesting one.
However, I think the self rightous cyclist is as bad as the self rightous car driver. I would say the point is we need to work together on the roads, or one of us is going to 'get dead'.
In this case, a cyclist buggered up. They need to accept they buggered up, and accept the verbal abuse (most probably the driver repositioned their mirror when they got home, and forgot about it). At the end of the day, it would have been an annoyance to both parties, but both are still alive and unharmed...let's just forget about it, and cycle better next time.
On a side note, any cyclist who thinks they ride 'perfectly' is deluded. I have been the victim of bad cycling, and bad driving.. but I have also noticed myself cycling badly / making bad judgements. When the latter happens, I take the verbal, and acknowledge I buggered up....knowing next time I will not make the same mistake.