That is easier said than done in some circumstances. I was driving I-80 in Wyoming doing about 65 in the left lane. The speed limit was 75. As I topped a gentle rise there was a car behind a car with a boat trailer stopped in the left lane. From the moment I saw it there was barely enough time to swerve into the right lane and avoid plowing into it. Had there been traffic in the right lane next to me I would have hit that mess before I could have touched the brakes. It's easier with a manual transmission. I've gotten into the habit of gently lifting my foot off the accelerator as I reach the top of hills. The car slows and I'm already halfway to hitting the brake if I have to.
People behind me get irritated, but I really don't care anymore. Besides, the cops always sit on the other side of a hill or curve. The first time my mother-in-law road with me I looked like I was psychic when after speeding for some time I slowed for a hill and other the other side sat a cop.
I don't know what difference it would have made in my case. I was driving my '59 pickup with a four speed, no time to shift, not even time to hit the brakes. The rise in the hill was so gradual it wasn't possible to see that it could hide a vehicle from sight. And I really doubt that anyone would slow down to 40 on an Interstate. That would in itself create a hazard.
The story this thread started with has the motorcycle following a truck obscuring the cyclist's view of the road ahead and the truck swerved to miss the girl's car at the last moment. As the prosecutor said, even if the cyclist had been doing the speed limit he would have had no time to react.