One of those leaving a comment said, "I always ride a little bit scared", meaning they pay attention when they are on the road, expecting the worst and always anticipating bad or stupid behaviour.
It's not only cyclists that end up seeing a lot of stupid motorist behaviour - I drove a truck part time for 4 years, and the amount of idiocy that I saw from my elevated cab convinced me that even the most brain dead window lickers are granted a licence these days. I lost count of the fools that, when approaching a red light, would speed up, over take me, then duck in front of my truck at the last moment. I would slam on the brakes and cringe, waiting for the sound of a car being compressed into half its normal length.
I always drove a truck a little bit scared - scared that I would smash a nuff-nuff and their car to bits one day, and that smash would be largely out of my control. Every time I climbed out of the cab, my back would be wet with sweat - partly from the physical effort of driving a truck with no air conditioning, no power steering, a crash gearbox and little insulation between driver and engine, but mainly from the stress of piloting it through a sea of fucking fucked fuckheads.
The other interesting statement made in that linked article is that "bikes were on the road before cars".