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by simook 3111 days ago
Going faster does not improve the speed of traffic. Matter of fact if everyone drove the actual speed limit we wouldn't have such a bad trafffic problem. Our infranstructure was designed to handle a range of speeds, primarily for the timing systems. When people drive outside those limits, that's when traffic patterns become unpredictable and/or unmanageable.

The slow drivers are no different than the fast drivers. Both of you are outliers and aren't easy to calculate in the timing algorithms.

imo, people are selfish when it comes to driving.

5 comments

> Going faster does not improve the speed of traffic.

The parent never said that.

When you merge on onto the freeway to need to merge at the fucking speed of traffic.

I've been in so many cases stuck behind a clueless oregon driver merging onto I-5(70mph) at 35-40mph while there's a fucking semi bearing down on us 1/4-1/8th of a mile away.

It's goddamn dangerous and putting people in situations where someone is going to get killed.

This behavior makes me a selfish driver, too. Doing 20 under what I’m doing when you hit the end of the ramp? Well, I’m sure as hell not letting you in front of me. If you can’t be bothered to do it right, I can’t be bothered, either.

Which doesn’t help traffic one iota.

You are not obligated to yield to traffic entering from an onramp. You are doing it right by not letting them in front of you.
Not obligated, no, but certainly the polite thing to do. Problem is in Seattle, what was a polite thing to do is now considered an obligation. “No matter how slow I’m going, you have to let me in” has been local culture for the seventeen years I’ve lived here, wrong as it might be. Which means when they’re creeping down the exit ramp, if they end up beside you they won’t even look when they move over. No, I am not exaggerating, they will blindly merge right into you if you don’t watch it.

So, no, one is not obligated to yield, but at some point you’ll do it anyway if you value your passenger side door panels.

I often see people refuse to move from far right lane and refuse to adjust their speed to accommodate drivers merging onto a 3+ lane highway/freeway. I don't know the laws on this one but it seems like a similar level of asshole behavior as staying in the passing lane despite an open lane to the right and faster cars behind. You may have the right of way but an action that's usually very simple for you can alleviate a situation that's usually difficult for the merger.
I often see people refuse to move from far right lane and refuse to adjust their speed to accommodate drivers merging onto a 3+ lane highway/freeway.

In Seattle, often times you can't move out of the lane, traffic's too thick. Which is why the person in the right lane needs to make accomodations to those merging, and the person merging needs to do their part by accelerating to speed of traffic. It's a cooperation, and when the mergers don't do their part it fucks it up for everyone else. I have to disrupt traffic flow because your Mustang can't accelerate to 60mph in a reasonable amount of time. Or I don't let you in, now everyone behind you on the exit ramp gets to slam on their brakes. Given the choice, I'll screw up the exit ramp by not yielding to a slow-poke rather than screw up multiple lanes on I-405 by slamming on my brakes or making a questionable lane change.

On the flip side, if I've accelerated to the speed of traffic flow and you don't want to let me in, I'll remind you that in the Chicago-style school of driving where I got my black belt, the turn signal is a warning and not a request.

EDIT: refuse to adjust their speed to accommodate drivers merging onto a 3+ lane highway/freeway

Wait a minute, what? The general traffic lanes have absolutely no obligation to adjust their speed to accommodate anything coming down the entrance ramp except an emergency vehicle. It is the responsibility of those merging from the entrance ramp to adjust their speed to the flow of traffic. It's in the driver's manual of three states I've lived in, and I'd be surprised if it weren't universal.

Nope, they're under no right to let you in, merging traffic yields.

Consider if you were driving a 80klb GVWR semi. If the law required you to yield that could make for an incredibly dangerous situation.

What infuriates me the most is when some hot to trot jagoff passes me at the last second doing 80 freeway a, and then does 40 merging onto freeway b.

If I am out accelerating you in a goddamn ford fiesta which does 0-60 in 11 seconds... well you're probably not driving correctly.

FYI, mid-michigan also sucks for this sort of thing.

edit: Apparently wanting to see data is offensive to drivers on HN. /shrug
It's not just incident numbers, when you get two slow drivers/semis blocking the lanes you have a large number(10+ cars) that tend to tailgate way under safe following distances. I've seen 5 cars all stacked together under one car length on many occasions.

All it takes is one stupid/wrong move and you have a massive pileup.

Most of the speeding accidents I've seen along I-5 tend to be single car unless they cross the divider.

Whenever I see it happen I usually double my following distance and let all the idiots sort it out but most people just tend to put themselves in a position where they don't have an exit if something goes wrong.

I wouldn't be surprised if unsafe following distances is the #1 cause of accidents on the road, regardless of fast/slow speeds.
https://www.motorists.org/blog/speed-limits-slower-safer/ this has some good data. Going too fast or too slow are both dangerous. When merging on the highway, you should be at the speed of traffic to minimize risk.
Agreed completely. Furthermore, imo the worst are slow mergers and lane weavers. On both counts they're entering lanes of traffic at wildly different speeds, which not only creates more traffic but puts everyone at risk.

I don't mind speeding in the left lane if they're at a reasonable speed above their immediate right lane. If they're going 30 over what the one-right lane is going it's quite hazardous. Yet so many people feel justified. Selfish.

The trouble is that the left lane doubles as the diamond lane at rush hour.
Very regional, fwiw. I don't have those in my commutes, for example.
> The slow drivers are no different than the fast drivers

Bingo. You should be pissed at people who don't drive the speed limit.

Change that to median roadway speed, and I'll be on board. Speed limits are too often set by clueless folk for political concerns, rather than by traffic engineers for maximum throughput for a given safety factor.

There should be some allowance for ensuring that the median speeds of adjacent lanes have a good range separation. I can't even count how many times I have seen a tractor-trailer in the left lane at 70 mph passing a tractor-trailer in the right lane at 69 mph, as passenger cars stack up behind them. It creates a dangerous situation that I can only avoid by slowing down or exiting the roadway.

Speed limits should apply only to the rightmost lane, and additional lanes should be between 5 and 15 mph faster than the current speed of traffic in the lane to their right, regardless of their absolute speed. It makes sense, and it would improve traffic flow, but it can't become law because it would be too complicated for cops to enforce.

> I can't even count how many times I have seen a tractor-trailer in the left lane at 70 mph passing a tractor-trailer in the right lane at 69 mph, as passenger cars stack up behind them. It creates a dangerous situation that I can only avoid by slowing down or exiting the roadway.

Presuming the max speed was 70mph, your post epitomizes the real danger. Traffic should not stack up behind vehicles traveling at the maximum allowed speed. Or at least, it should not stack up in a dangerous way. Twenty vehicles stacked up at proper following distances, all traveling 70mph, is actually optimal. Yet you seem to disparage it. You will never achieve optimal traffic flow if the general attitude toward actual optimal patterns is disdain.

If the max speed limit was above 70mph, ignore the preceding paragraph.

> proper following distances, all traveling 70mph

Hi. Welcome to Earth. It looks like you missed orientation.

Humans drive at different speeds, and usually follow too closely. We have recognized this species-wide problem, and are currently trying to build driving robots that will reduce the impact. Until they are ready, every collision you may see on the road was likely caused by a human driving non-optimally.

Therefore, rational drivers must presume that the other vehicles on the road may possibly behave irrationally, and therefore must introduce a safety margin for the incorrect behavior of other drivers in addition to the margin defined by their own capabilities.

Show me a train of 20 cars moving at 70 mph with less than 1 second of separation between them, and I'm just going to ease off the accelerator, and maybe look for my next rest stop, until those lunatics are far enough ahead that I'll possibly learn about their 6-vehicle pile-up early enough to detour around it. The only way that is optimal is if there are zero humans in it.

Welcome to the 21st century. Times have changed. Driving robots are now a reality. Adaptive cruise is a real thing, and the most well-known adaptive cruise systems slow down to adjust to traffic speeds, not speed up and pass.

In fact, the most well known system made an adjustment some time ago that it would no longer exceed the legal speed limit.

> rational drivers must presume that the other vehicles on the road may possibly behave irrationally, and therefore must introduce a safety margin for the incorrect behavior of other drivers in addition to the margin defined by their own capabilities.

Exactly. So slow down. Join the train of cars instead of trying to pass them. Maintain a safe distance and don't worry that you will be late. You won't. 20 cars driving 70mph is better than 10 cars driving 80, one driving 85, five driving 75, two driving 90, and two driving 70. It is better for all of those cars, not just the two driving 70. They will all be safer, and they will all arrive at their destinations within 60 seconds of when they would have.

Humans are not machines, of course. But they can work on one important attribute with which every automated vehicle should be programmed: patience. In a world where human drivers increasingly share the road with robots, human patience must adapt.

"Proper following distances" absolutely does not mean "with less than 1 second of separation between them"!

"Proper following distances" means "you can react and stop in time to prevent a collision if the car in front of you brakes very hard".

Ripped from a wiki article on the topic:

"

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 am describing what people actually do, not what they should do. I think everybody knows that they shouldn't tailgate, but they just do it anyway, because "F U get out of my way".
> because it would be too complicated for cops to enforce.

The only reason speed limits get so much focus is that they are so easy to enforce.

Because of that, they have essentially become a direct-to-police tax, rather than something useful.

We have traffic due to lack of scientific understanding. http://www.science20.com/gerhard_adam/driving_traffic_and_tw...

Traffic = Flow Rate (How many cars pass per minute pass a specific point)

Traffic Solution is maintain proper distance. 2 seconds in good weather and 4 seconds when hazardous or 10 seconds when extremely unsafe weather/conditions.

When people increase the distance between cars during traffic causes the traffic behind to eventually come to a stop.

Thats why at any given speed, there is a maximum capacity of any road that when surpassed causes traffic, i.e. people speeding up and slowing down due to differences in each other's acceleration. This is unavoidable and the only solutions involve increasing everyone's speed, reducing # of vehicles, or making the road bigger.
Traffic happens when distances are increased. Someone sees a slight slow down and they then slow down and give 20 seconds of space (I have seen cars and trucks give 200+ feet of distance for some odd reason. Then the flow is cut down to 10 cars a minute instead of 120.
Yes, but you can't fix that. And the faster you go, the longer it takes to stop (to the power of 2). Rule of thumb I've read is 1 car length for every 10mph to be able to stop in time in case if accident up ahead.

Obviously safety gets triaged with need to get somewhere in a reasonable amount of time, but at a certain point you hit a maximum and since we can't drive in unison, there will be a rubber banding effect.

You can't expect people to go the same, or similar speeds.

There will always be trucks going slower, and always people who feel comfortable at much higher speeds.

Going different speeds is what multiple lanes are for.

The problem is that multiple lanes lose their value when two cars are driving side-by-side at the same speed. If the left car speeds up for a short period, then moves to the right, traffic will be able to circulate, creating more distance between cars, and fewer instances of significant speed difference in a close range over a period of time.

The problem is that speed itself is quantifiable, so police focus on it way more than is helpful. To legitimize speed tickets, there have been years of propaganda teaching people that slower = better, so those who want to drive slow feel vindicated, and those who understand traffic flow are frustrated.