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by kurupt213 1439 days ago
There are valid reasons for exceeding the speed limit
3 comments

A _vast_ majority of exceeding the speed limit is not done for valid reasons.
I'd argue that it's almost never correct to drive the speed limit. In the US at least they are almost universally slower than the natural speed of the road by 5-10 mph and everyone speeds a bit all the time.
This is a bit preposterous. First off, do you know how speeds are set? Civil engineers build a road, and then figure out the 85th percentile speed for that road based on sample data collected. [0]

That's a couple things:

1. Not based on any actual design criteria for the road

2. Assumes that 85% of drivers are somehow more knowledgeable than the engineers who are supposed to be designing our roads and transportation.

The claim that you should be always able to go 5-10mph above the limit seems to be a mythos invented in and ingrained in the fabric of the American psyche. Better approaches exist than to just pick a popularity consensus from a sample of random drivers in a study (who are predisposed to going faster, often because the study is done before full levels of traffic set in).

[0] https://www.strongtowns.org/journal/2020/7/24/understanding-...

> The claim that you should be always able to go 5-10mph above the limit seems to be a mythos invented in and ingrained in the fabric of the American psyche.

I think you're misinterpreting the parent commenter. They said that, in the U.S., speed limits are almost universally slower than the natural (i.e. prevailing) speed of traffic by 5-10 MPH, and so everyone driving at the prevailing speed of traffic is inevitably exceeding the posted speed limit by a bit.

That is definitely true, at least if you're not in the rightmost lane of traffic sandwiched between semis and box trucks. 75-80 MPH in 70 MPH zones is common, and it's not unusual to see people driving 85+ MPH.

> That is definitely true, at least if you're not in the rightmost lane of traffic sandwiched between semis and box trucks. 75-80 MPH in 70 MPH zones is common, and it's not unusual to see people driving 85+ MPH.

As an observation I'd agree. However, my impression of the parent commenter was that they implied that 5-10mph over the speed limit is the correct way to drive. Were that true, why wouldn't we just set the limit anyways? How did that limit get chosen?

Again, this goes back to the 85th percentile - the ways in which we decide how fast to go on a road or street are wrong. Of course, there's two things going on in this thread:

- Using tech to warn / limit drivers from being able to speed over an agreed upon limit.

- Engineering our roads so that the intended speed matches the prevailing speed of traffic.

Now I'm more in the second camp on this one than the first, I'll admit, but I don't think that we should just sit by and accept "some people speed, therefore we should all go faster" as a given. I have definitely witnessed people going 85+ MPH, especially if you're on an interstate far away from any city. However, this is not the norm and not really where the tech in TFA is going to be deployed.

Either way, the issue I take is with moralizing going faster than the speed limit. You might say it's the flow of traffic, but that just smells like justifying something that most drivers already want to do (go faster), instead of understanding the action (speeding) and its effect on the environment around us (increased danger, increased fuel consumption, increased noise pollution, etc).

Things must be crashing and burning over there in California with all the driverless cars.

Or you know, cars will just go the speed limit, 10 years from now and you won't even remember your brain simulated a shitty PID controller to hit some speed number subject to your irrational whims.

They won't. The rich won't let you dictate how fast they can go, so ferraris will be exempt. The upper classes will 'illegaly' turn off the limiter on their teslas 250d, but no sane sheriff will dare to enforce the law here. Middle class will be loosely complaint, the same way they observe the speed limit laws today. Only the lower classes will have no choice but to drive the 'chopper cars'.
But if new cars were incapable of exceeding the limit, that wouldn't be true for long.
There are still tons of cars from the 90's and early 2000's on the road (in particular the '01 Camry), it'll be at least 20-30 years and anyone with a new car being limited is just going to be harassed for driving way too slow relative to traffic.
And even once this is over, I think it's pretty often the speed limits and not the people driving over them that are in the wrong. I don't think slowing everyone down is a useful goal unless we adjust the limits up first.
I agree, but I don't think that would be a good thing.

I suppose if the end result was that speed limits got adjusted up 5-10 mph to match the speed of the road it would be fine. I doubt this would happen in general, and I know it wouldn't happen universally.

That might be right, but suddenly enforcing a limit when overtaking can easily cause an accident.

And speeding might not be that bad, many of them seem outdated or plain wrong, to the point where it's safe to go 10-20km/h faster, and in some places ridiculous not to go faster.

Come to Houston. You better be speeding on the highway or you're in danger. When everyone is speeding, and you're doing 60mph, you're a danger to yourself and everyone around you.
That’s one reason I’m avoiding your shithole of a country.
Way to add discord to the discussion.
Is Propping up oil company profits one of those reasons? Driving the speed limit would likely drive gas prices down due to a >10% decrease in demand

Or according to this site maybe >20% https://www.mpgforspeed.com/

People who speed don’t really mind the gas prices. Because Speeding is like paying $1.20 extra per gallon in CA

Name two
Passing a slow car (driving below the limit) on two lane undivided highway. You could pass them at the speed limit, but its safer to just speed up while passing the car and then reduce your speed when you are back in your lane.

I had to do this multiple times passing RVs while on a road trip this weekend.

Ok, but legally you aren't allowed to do that.

Also why is it safer?

To me a predictable speed would be safer.

It's legal, at least in the US, if there is a dotted or broken yellow line between the two lanes, the opposite lane is clear, and you have enough time/space to complete the overtaking before it swaps back to solid yellow. For obvious reasons, you generally want to spend as little time as possible in a lane that has traffic coming at you head-on.
>Also why is it safer?

Because you spend less time and less distance in the "wrong" lane.

Which you should not have entered in the first place.
Your opinion is asinine. If using the lane at that time/place to pass was not suitable it wouldn't be signed/marked for such. Increasing the time it takes for people to execute a pass is a regression in safety from the status quo.
Safety when overtaking. Wife in labor.
Just call an ambulance (we are speaking about Europe here).
Dunno how exactly these systems work, but I assume it wasn't designed by idiots who never driven a car before and accounts overtaking. Warning should be only ON when sustaining the speed, not for few seconds.
Driving someone sick/injured to hospital from a rural area.
I'll name one: being significantly different from the speed of surrounding cars irrespective of speed limits results in more accidents.

Differential speed kills.

Avoiding a collision

Operating an emergency vehicle

No.
1. it's fun 2. also speed limits are stupid