Reread post #26........there was no slow down of the pick up truck that slammed into the back of my friends SUV while my friend was down to 15 MPH...........
Exactly my point. I would rather have that truck closing at a relative rate of 10 mph (Him at 70, me at 60 and decelerating slowly), than have him closing at a relative rate of 55 mph (Him at 70, me at 15). Even if he hits you, it is a bump, not a crush. And because he has time, closing at such a slow relative speed, who knows, he might just look up from his phone long enough to avoid the collision.
I do not mean to denigrate the memory of your friend. Not all tragedies can be avoided, and it sounds like your friend's situation was one of those.
This defensive driving stuff is not the norm, but it works for me. I hope it might work for you, too. But I am sorry for your loss.