Well, apart from it being a good place to mount the camera which had a flat battery by this point, I have a feeling it saved me a trip to a hospital at the very least.
Quick sum up - I got hit across the back of the head by a high mounted van wing mirror at a speed differential of around 40mph.
Longer - I crested a hump back bridge towards the end of a long ride (for me) of 25 miles. The bridge is pretty narrow and double white lines adorn the roadway. I take primary when crossing it to avoid stupid passes. After the crest I'll move over if I see nothing coming the other way.
Today I was a bit slower than usual due to muscles claiming that 100 miles in 3 days is too much (I'm trying to work up for a 70 mile day towing a trailer in the summer). I moved over as I sped up and before I saw the Yaris coming the other way.
A good thing I did. A van came over the bridge behind me at full revs and apparently trying to catch air. If any brain cells in the driver's brain did engage, I can only assume they went "Oh S***" as he realised he was landing with no control head on into a Yaris or rear ending a bike.
So he did the only *sensible* thing *cough*. He accelerated through the erm... gap.
I got a very hard smack on the head from his wing mirror and the Yaris ended up taking emergency avoiding action onto the pavement.
The lady driving the Yaris blew out a tyre and may have knackered some suspension.
The van shattered his wing mirror and passenger window (the mounting sprang round on impact and caved it in.).
I have the attached image of my helmet.
I *think* that's an imprint of the interior workings of the mirror where it hasn't just gone to pieces vertically.
I'm not an advocate of compulsory helmets. The chances of this incident are stupidly slim that this isn't an argument in favour of wearing them all the time either (even when riding a bike!)
I get the feeling that something taking lots of the impact, distributing the energy and breaking apart that wasn't my skull was probably a good thing. It's also occurred to me that the 12mph rating is into the ground. That's a sudden stop. An estimated 40mph energy differential is a lot less energy given that the impacting item was sprung and only a few Kg in spite of what it was attached to.
Tomorrow... I may not be out on my bike. I have a bit of a headache. The day after. I'll be out. I won't be wearing a helmet. I haven't got a spare.