For large sections of many highways at rush hour, there is essentially never a space to comfortably merge into. You have to essentially make spaces to merge into whether because someone sees you signal and lets you in or someone isn't really paying attention and has let a gap open up.
The thing that blocks up traffic at a merge is when people can't get over smoothly.
If everyone gets over at the first opportunity, then things go fine. The empty lane isn't wasted, it absorbs brief bursts in traffic that need more time to get over. But even if it was wasted, that wouldn't be a big deal. A 5-mile long section with fewer lanes and a 5.5-mile long section with fewer lanes will have almost the same throughput.
Everyone staying split across two lanes until the end and aligning themselves to do a clean zipper merge also goes fine.
What makes everything go wrong is when people drive down the nice empty lane that's ending and intend to do a normal merge at the end, but they don't start it early enough. Then everything slows down as they squeeze over.
What I see here in Maryland is that there is plenty of room for every car to merge onto the highway, except that nobody moves left to let them in. Why would you stay in a lane where you can see you're going to be slowed down and even have to brake, when you could move over, maintain your speed, and make room for others? I don't know, but that seems to be the majority's instinct.
A lot more effort needs to go into road design too though. The best merge is the one you never even need to do.
For instance, I’ve seen ridiculous things like roads that open up two new lanes, only to remove BOTH of the new lanes within a half mile or so. (There wasn’t even an exit in between, just space they decided to use.) Predictably, that creates an insane cluster of traffic every single day in rush hour that could have been 100% avoided by simply not offering either of the bait lanes to begin with!
I also do not understand why so many merges have one tiny sign as the ONLY indication of a merge, sometimes over a very short distance. What, you just spent a few million on a road and you can’t afford 2 or 3 signs per merge? Put them up! Give people every chance to move. Surely it can’t hurt.
There are known choke points where traffic is forced to merge. There is the occasional tourist, but rush hour happens every weekday. People know about these merge points, see traffic backing up in all lanes, and will still jump into the lane about to end trying to rush around a few extra cars.
Are you allowing enough space in front of you for cars to merge in without wedging themselves in front of you?
That's the worst problem I see around here -- cars in the freeway running bumper to bumper, and then a block of 3 or 5 cars also running bumper to bumper trying to force their way in, but none of the cars really leave enough room for a smooth merge, so the cars on the freeway end up hitting the brakes when the merging cars force their way in.
Where I live, all too often there just isn't any runway to do this. When you're trying to merge, say, here: https://binged.it/2DTnemt then all you can really do is rip right into traffic and people will just have to make space. It's the worst possible layout for supporting a smooth traffic flow, and it baffles me that they don't lay the extra 200ft of asphalt to improve this, especially in a state that has a DOT that does know how to apply innovative solutions to increase traffic flow like SPUIs and CFIs.
The problem with early merges is that there's no way people that merge in are at highway speeds when they merge, causing everyone behind them to have to slow down, which eventually can cause traffic jams. Just use the whole lane, make SURE you're going the same speed as the rest of traffic. The confusion there is that because of an existing jam or slowdown, people are already at a matching speed at the start of the on ramp. Or so they think.
This comes up often, but you gotta think about what would happen if everyone suddenly tripled the gap they leave in front of them. The same road surface would suddenly have 1/3 the throughput. I shudder to think what kind of traffic jam / commute time that would lead to at the edges of the road network.
I do appreaciate when people drive densely packed and I try to do the same (up to a safety limit). For merging there are turn signals.
The problem is that allowing merges incentivizes zooming ahead in the merge lane, which should result in there still being drivers who can't merge, creating the jam. I don't have a good solution for this.
Sometimes there is an unplanned need to merge, for example if one lane is closed due to construction or an accident (as I think is indicated in the video).
Do you never merge or change lanes in heavy traffic? Because if you’ve ever done any of those things, you rely on people leaving space and letting you in. Why deny others the same opportunities?
Driving in traffic is a cooperative activity. The only times you don’t need to accommodate and be accommodated by other drivers are when there are hardly any around.
But if you're trying to merge on, whether or not you have to stop before merging is not totally in your control. Specifically, if the right lane is packed, you may have to stop if there is no opening as you pull up. Then it will be harder to merge in, not only because you are starting from zero velocity but also because the lane is packed.
That is why I think people should not get in the right lane on a highway unless they are about to get off.
To an extent I think you're right and some people will do it regardless. On the other hand, smoothly flowing traffic creates an incentive to not zoom ahead in the merge lane. There's less of a feeling of a need to cut ahead and people don't seem to do it as much when there isn't already a jam. (That is, the jam provides an incentive to cut in front of everyone)
And if people were to implement this strategy, the provided space gives an incentive for those zooming ahead to merge a little sooner rather than risk waiting half a minute for someone to let them in right at the exit. It's been my experience that most of the "cheaters" will merge a little sooner if there's space rather than zoom up right to the end. They'll still be passing you, which is IMO aggravating, but at least things will move a little sooner.
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