Because that would force the idiots doing it to engage their fleshy equivalent of self driving mode instead of blithely following you and hoping you move out of their way.
A friend of mine has a passive-aggressive way of dealing with bumper-crowding jackwagons- he just gradually slows down until the tailgater gets pissed off enough to change lanes. Can’t really say I approve of it, because that can wind people pretty fast. Getting brake-checked is never fun.
I’ve learned to drive very defensively, and to not be the agressor unless I’m forced into it, in which case I make damned sure people back off. (not necessarily brake checking, but a touch of weaving like I’m in NASCAR and getting the tires up to temperature while staying in my lane tends to force everyone in the three lanes behind me to back. the. fuck. OFF. (and I’ve only ever gotten pulled over ONCE for pulling that stunt, and the nice officer gave me a warning, probably because the person I pulled it on was being a Class A Jackass.)
