Originally Posted By: Cujet
From a traffic engineering point of view, it's best to smoothly merge. Unfortunately, many drivers fail to accelerate, possibly feeling that acceleration is "bad" or "wasteful" and to be avoided.
The problem on many limited access highways is that traffic is over capacity. As long as everyone moves quickly, and follows closely, traffic does not backup. What many don't understand is that just one slower motorist can cause traffic hysteresis, (the accordion effect, or elastic band effect) rapidly leading to a standstill.
It's common around here for folks to enter and exit the 65+70MPH interstate at 43MPH. Despite half mile long ramps. Ramps long enough to allow fully laden trucks to achieve highway speeds.
Furthermore, drivers that insist on 2 seconds of following distance when a highway is over capacity, are very likely the ones causing the accidents behind.
Interesting study:
http://iopscience.iop.org/article/10.1088/1367-2630/10/3/033001
And some movies from the study that show exactly how it happens in test conditions.
http://iopscience.iop.org/article/10.1088/1367-2630/10/3/033001/data
Sometimes the only way to drive "safe" is to drive a little "dangerously".
People think I'm nuts when I'm hauling a big load on a trailer. I do everything I can to block traffic from entering in on my left
as long as I am going the speed of traffic.
Why? If I don't do that, people behind me and to the left of me assume that there is this amazing, clear, highway to heaven in front of me that I am going too slow to take advantage of. One idiot will cut me off and slam his brakes upon realizing there is traffic going the same speed in front of me. The next idiot comes, and the next, and the next, and they all nearly crash into each other. Then, I'm left to plow into them, weighing 12 tons.
People not going fast enough entering the highway are a real hazard. Not just because traffic has to slow to match them, but because these people have a notoriously bad habit of simply choosing to throw themselves into the fast traffic without regard, after choosing not to match traffic.
Refusing to cooperate with a common sense system to make life easier for everyone is becoming all too common these days.