I had just about the exact accident that haithabu had, but luckily for me I was in my car, not riding my bike.
Slow traffic , a large conversion van just a car length ahead on my right slows to a stop , which I took (wrongly) as a move for it to turn into a parking lot. (I did know there was a driveway there) Instead , and elderly lady in a mid-sized car pulls out past the van , stopping right in front of me.
Nothing to do but slam on the brakes and hope. I likely hit her car at under 1 mile an hour, so thinking if the side of her car was just a line on the road, I would have stopped just a few inches over it. But of course, it was a solid object , so she ended up with a nice dent in her door, and my car (with a large rubber bumper) escaped without any visable damage.
The sad part here is I know if I were on my bike .. I might have made the same mistake. Luckily this imprinted this particular scenario in my mind, so I know now that if simular circumstances were to occour again, I will do the right thing and either stop along with the vision blocking van, or at least slow to point that I know I would be able to stop if something jumped out in front of it.
Haithabu's account should be the lesson for all those that have not envisioned this scenario yet. If a vehicle in another lane slows or stops, there is likely a reason, and don't assume to know what it is.
In my case also , the driver of the van actualy waved the old lady on...So I am not sure if he thought she was just going to pull in front of him and into the same lane , or if he was just too stupid to think of checking his mirrors for cars coming in the lane next to him, or what.
This should also stress the importance of proper gear, and that you can get hurt pretty badly even going fairly slow. Many riders rationalize that they do not need their gear just to run up to the store for a pack of ciggerettes, it's only 2 blocks away and they won't be going over 30 mph. Oddly this seems to be exactly when something goes wrong. Most riders are not hurt speeding down the highway, it is usualy within 5 miles of home and on more residential streets.
Haithabu , I hope you both heal well and fully, and that you do decide to keep that full face helmet as your full time headgear.