He was on a slightly older BMW with the hard plastic paniers, he was about 2 - 2½ car lengths in front of me and we were in the outside lane. A woman in a black commodore just change lanes into him, point of contact being the panier (luckily), he must have been at her B pillar when she started to move. He didn't seem to swerve at all to avoid her (maybe he wasn't looking at 90degs to hsi bike), but perhaps he accelerated to try and get past her. Anyway, she clipped his panier with a reasonable wack, it didn't break, but he wobbled a fair bit and then looked around at her. He went to the outside breakdown lane and stopped. She looked carefully behind her as I was passing her (thankfully) and then pulled over. He seemed fine, she was probably pooping herself. At least it ended with no-one hurt. Can't be careful enough out there people.