That's what we learned in Driver's Ed too. But now days, I think they are teaching the 2 second rule. Which is, when the vehicle in front of you passes an object, such as a sign post, it should be at least 2 seconds before you pass that same object. That works for any speed from 10 mph on up. At 60 mph, you would be following at 176 feet, or about 59 yards.What I learned in Driver's Ed in HS. I don't think it is even taught anymore, which might be part (but not all) of the problem.