It takes about a 100 yards -- a full football field -- for a normal passenger car to react and come to a complete stop.
https://www.qld.gov.au/transport/safety/road-safety/driving-...
This is equivalent to 4 full seconds of following distance, which is double the typical 2-second-rule recommended by transportation governing bodies.
https://en.wikipedia.org/wiki/Two-second_rule
If your suggestion was taken seriously, it would literally halve the carrying capacity of our highways.
Luckily, situations where the vehicle in front of you comes to an instantaneous stop are extraordinarily rare, basically requiring a head-on collision.
> The two-second rule tells a defensive driver the minimum distance needed to reduce the risk of collision under ideal driving conditions. The allotted two-seconds is a safety buffer, to allow the following driver time to respond. [emphasis mine]
> Some authorities regard two seconds as inadequate, and recommend a three-second rule. […] The United States National Safety Council suggests that a three-second rule—with increases of one second per factor of driving difficulty—is more appropriate. Factors that make driving more difficult include poor lighting conditions (dawn and dusk are the most common); inclement weather (ice, rain, snow, fog, etc.), adverse traffic mix (heavy vehicles, slow vehicles, impaired drivers, pedestrians, bicyclists, etc.), and personal condition (fatigue, sleepiness, drug-related loss of response time, distracting thoughts, etc.). For example, a fatigued driver piloting a car in rainy weather at dusk would do well to observe a six-second following distance, rather than the basic three-second gap.
I've had to veer to avoid accidents. At least three sitautions I can remember on the interstate: a semi truck tire blowout in front of me leaving large parts of the tire in my lane; a bike rack with several bikes falling off the back of a car in front of me; a truck in front of me veering around a obstacle (it appeared to be a pickup truck bed liner) I was blind to because I couldn't see beyond the truck in front of me.
I was lucky to avoid all of these because I had a parallel lane or shoulder I could escape into. When I drive now, if it's congested I leave extra following diatance. If that reduces the road capacity so be it. Compared to drivers who follow much too closely (which itself causes sudden slowdowns since they tend to over brake) or who drive in the wrong lane for their speed, I don't think I'm the person you need to worry about.
FWIW, I haven't been in an accident in over 25 years.
Your strategy to take all possible precautions regardless of large efficiency loss doesn't align with the reasonable tradeoffs that the vast majority of humans make.
On a non-congested road, there's no excuse for putting sufficient distance between you and the car in front.
If you can't see 200 yards ahead, you should not be travelling at a speed which precludes you from stopping within 200 yards.
On a single lane uncongested road, there's no excuse for putting a reasonable (at least 3 second) gap between you and the vehicle in front.
Huh? The whole context of this discussion starting from js2's comment is about exactly how far is should be, and in particular whether 2 seconds or 4 seconds (which at highway speeds is 50 yards vs. 100 yards) is more reasonable as a rule of thumb. As you can see from my link, most government safety organizations recommend 2 or 3 seconds in good weather.
Or veer out of the way of an obstacle you can't see, leaving you to either similarly veer or collide with it. IOW, do not assume you only need to account for your own reaction time; rather assume the vehicle in front of you can instantly stop moving and you must account for both your reaction time and your vehicle's stopping distance.