It's been six months or so since, following the example of Bob T, I upgraded my visibility quotient.
Those six months have made a believer out of me! It's totally comforting to glance down when I'm riding - particularly at the times of day when there's not much sunlight - and see that hi-viz stuff almost glowing-in-the-dark!
Here's the bottom line:
a) I optimistically assume that no motorist will deliberately run into a cyclist. (There are exceptions, but they are rare enough to be statistically irrelevant, I'm thinking.)
b) If a motorist fails to see you, all bets are off! That motorist might be impaired, or distracted. (S)he might be clicky-clickin' on a little keyboard nowadays, and only occasionally peeking up at the road. (That kind of driver is much more prevalent than the murderous psycho-driver.) So anything you can do to increase the chance that you get spotted is an absolutely good thing!
Before I "saw the light," I'd tend to wear "bright or light-colored clothes," because it's common sense. But I'm totally on board nowadays with 100% as-bright-as-possible. It might just be my imagination, but I sure feel like "close calls" are down significantly since I did the upgrade. (In the photo I'm modeling my everyday riding attire, at least this time of year - a hi-viz jacket, and a mesh ANSI vest on top, with big wide reflective strips and contrasting color strips.)
OH! And bright blinky lights, front and rear. Lights are good - bright clothes are good - both combined are good-plus!
I'm grateful to Bob for preachin' the word... and I'm grateful I had the common sense to pay heed.