As usual, we have good points being brought up by both forum veterans and noobs - thank you for your thoughts.
I want to tie them back to the topic of accidents and driving in my OP:
Driver training courses (I happen to be reviewing a motorcycling guidebook and various rider magazines presently) introduce the topic of 'panic stops' and defensive driving by emphasizing that an alert operator who is paying attention and reacting accordingly to conditions around them is going to drastically reduce the likelihood of a sudden catastrophe that comes down to habits [reactions] and luck to survive, because an attentive operator is looking far enough ahead to prevent bad things from developing in the first place.
The common exclamation "I didn't have time to react!" is very often a rationalization of "My attention was elsewhere" or "I was moving faster than I was thinking". [If you'd been ready to apply the brakes before that blind turn, you would have stopped 40 feet sooner]
As with safety behind the wheel, so with safety while traveling as a tourist/traveler/etc. If your attention is where it needs to be and your preparation was sufficient, you are much less likely to run into trouble in the first place.
I don't think anyone will argue with me about that (ha! of course you will) but take it a step further: when we're traveling, we are usually on vacation. "On vacation" by many people's definition means taking it easy and not having to worry about things that you normally worry about -- not just no cleaning the dishes or the shopping but no (or minimal) adulting at all.
~Acting responsibly is for people who aren't on vacation, amirite?~
So if your mindset and your situation is all trending toward letting it all hang out, then why expect whatever is hanging out won't get clipped?
We've reached this point in the many many postings regarding pickpocketing before: why do things differently while away from how you do them at home, because when you're away you are unable to 'read' the environs as well as you can at home and you can more easily be spotted by the pros. But it's more than that: you are on vacation, so you shouldn't have to be being careful and attentive because only people who aren't on vacation should have to be careful and attentive.
(This is why RS has settled on the final version of his pitch for using a moneybelt and small wallet/purse -- so that you don't have to be careful and attentive, and when a stranger's hand is in your pocket you can treat it like part of the adventure.)
Pile on top of this the mass media attention focus on terrorism and manifs and you have a perfect storm of the spotlight that brightens up the wrong thing in the scene.