* The 3 second rule I cited: "To avoid tailgating, use the “3 second rule”: when the vehicle ahead of you passes a certain point, such as a sign, count “one-thousand-one, one-thousand- two, one-thousand-three.” This takes approximately 3 seconds. If you pass the same point before you finish counting, you are following too closely." https://www.dmv.ca.gov/portal/handbook/california-driver-han...
* Real-world stopping distances being longer than 3 seconds (3 seconds * 55MPH = 242 feet) -- "Assuming you have good tires, brakes, and dry pavement: At 55 mph, it takes about 400 feet to react and bring your vehicle to a complete stop."
If someone dives and brakes in front of you, with a slower starting speed and equivalent or better brakes: you're a-gonna hit them. And no one seriously proposes that you should never drive faster than the lane next to you, which would be the only way to avoid this.
assuming you are in California: https://www.dmv.ca.gov/portal/handbook/california-driver-han...
operating a motor vehicle in the United States requires that you have this entire booklet (or that of another state; they are all nearly identical) memorized, cover to cover.