Hawkeye08's study points to a number of variables that contribute to reaction time. Driver age, experience, familiarity with equipment, visual acuity, level of alertness/fatigue, distractions, vehicle speed, and weather conditions.
When I read it, it still seems to lean to reaction times of "1.75 sec (daytime) and 2.5 sec (nightime)" as "good places to start" in the summary.
It mentions the 3M company's study findings of
"at night, when a tractor-semitrailer is blocking the road, motorists must identify the problem when they are one-quarter mile away. Therefore, in the 14.5 seconds necessary to see, perceive (recognize), decide what to do, and then do it, a vehicle will travel 1,276 feet. If the recognition begins a quarter mile away (1,320 ft), the motorist has a "cushion" of 44 feet."
But, of course, 3M manufactures reflective tape that can be applied around the backs and sides of semi trailers. If the study they funded just happens to lead to federal regulations that all of the many thousands of trailers in the country are required to be outlined with the stuff...well, no one would ever think a company would go so far as to fudge numbers to drive up sales

.
And its hard to tell in an online forum, but I'm assuming many posters here are tongue-in-cheek about microwaves and ground penetrating radar.
I would imagine those devices cost more than my tractor. As far as what could be added to a tractor
practically, I dunno. Like you said, most people don't even bother with tilt meters (including me). I would venture to guess if tractors started coming to market with kill switches/overrides, many users would disable them. <shrug>