Wayback.. was crossing San Pablo Ave. (wide-street) in Berkeley, enroute to work Person in crosswalk, cars stopped. Then someone drove through, hit moi + Vincent.
I was scooped up to bounce off perp's windshield, land on road/flat on back (head in-line ..a Good thing.)

As I lit, noted hmmm.. nothing broken, not even a bruise.. Interesting!
I was wearing a Brit "Corker", an early rudimentary head-cover not unlike a pith helmet.
The effect on landing was: head might as well have hit a rather stiff pillow, ..a Very-good thing.

As I got up, rather quickly ..my first thought was: this jerk prolly thinks I Be Daid (window bounce & all..)
As I approached the side-window I said, "Your insurance Co. will be damn glad I wear this helmet.. He. Was. ashen ... ...
(Because it was clear, He Got the Message of utter idiocy, I did not add the nearly mandatory "... you motherfucker!")




In the event, the settlement got me a brand new Black Lightning racing front-wheel/Borrani rims, Magnesium-alloy brake plates etc. and a passel of other goodies,
from good-ol Conway Motors Ltd. (of Shepherds Bush) and mail *exchanges with a neat guy/later friend, who meticulously sent along every item, on down to the 'tiny' bits.
* 'Ultimo. Proximo' ..added to vocabulary of Brit-write-speak du jour :-)

A few years later, I picked up my new Red A-H Sprite from Sid Broomfield, (Also an Austin broker.) He aimed me at Maidenhead, where en passant, I saw in yard
(it was a Sunday) heaps of vari-colured Sprite bodies ergo, warm-fuzzies. Euro Tour! Day 2. Got back to S. Bush o'nite place after wrong-side navigation all day. ✓

Synchronicity, eh? (Believe I had ordered the Corker from Conways earlier, but not sure..)

tl;dr
In the case of all vehicles with 2 degrees-of-Freedom: in a 3-D world: PHYSICS RULEZ!
But note also, in a recent PBS program re all those drain-bamaged idiot-Football young-uns, a simply superb demo re brain damage was shown:

Eggs were placed in an expensive 'Halliburton'-type alloy case, with form-fitting soft insert. The case was then tossed-all-around [as we all Know UPS does on a daily basis] ... and the case opened.
The eggs were pristine, as expected. 'Gramma' then sez, "I'd like a couple over-easy. please."

Alas, the yolk was sprinkled uniformly throughout. Nuff said? OK more:
all those neurons/synapses and er, interstitial materials which make a brain-a-Brain: are represented by that macerated yolk. Bitchin Helmets save skin & head-bones in almost ludicrous events, BUT..
Even the Best helmet Won't Save Your Yolk, however pretty-afterwards be the container. Only being 100.0% attentive, physics-ept and Wanting to Live ..gives some of us an edge
(I still be here, after all, with no brain damage at all at all at a


Ed: PS
In early days, Murican cyclists had yet to ponder.. the Fact that you can fracture skull/do whatever to innards ... walking. In time, the Fact dawnwd. Early small group I often went with through the swervery didn't guffaw at my sissy-headgear, but gradually adapted end adopted; helmets didn't cost a small ransom then, etc.

I never had to 'test' any of the later models, but that's just the Luck of the draw, and a realization that, if you plan to careen about on the World'sFstestStandardMotorcycleâ„¢, bunkie? try and [math]beat them Odds, eh?[/math]