There is approximately 0% chance that the speed limit decreed by faceless bureaucrats is the optimal speed for the current circumstances on a given road.
It has always seemed strange to me that restrictive speed limits persist in a supposedly democratic nation despite the functionally unanimous opinion of the citizenry, expressed through actual driving behavior, that the legally prescribed safety margins are excessive. I doubt you could find any other issue on which Americans of varying political persuasions would demonstrate such a high level of practical agreement.
In comment threads like these, one invariably views vigorous venting of virtuous vitriol versus the vice of velocity, but simply getting out on the road and having a look around - pretty much anywhere in the country - will show that such opinions must either be hypocritical or held by a small minority.
People are bad at risk management. I see oodles of people making wild decisions in their cars (sweeping across 4 lanes at once, backing up on the highway shoulder to return to a missed exit). The norm for trailing the car in front of you is also way way too short based on real physical limitations of braking.
Speed limits can also exist for reasons beyond the safety of drivers. There are roads around me that are wide, straight, and empty enough to comfortably drive 40mph but are right next to a school. The school-zone limit exists to provide extra safety for children who might foolishly step into the road very suddenly.
You're the one calling them faceless bureaucrats. Most speed limits are set in place by a mix of safety boards and urban planners, who do take these limits into account. Explain to me what makes them faceless and detached from the situation?
> Explain to me what makes them faceless and detached from the situation?
The fact that they’re not there.
The idea that the same speed is appropriate at 9am when kids are crossing the street going to school and 2am when there’s noone there and no cars parked on the side of the road, is insane beyond belief.
Speed limits are generally repressive and mostly just a tax collection scheme (though I strongly support most daytime city speed limits!)
No speed limits anywhere, or at least no enforcement.
As I said above, speed limits are repressive and a way for the government to bully its citizens and extract money from them. If the government actually wanted to solve the problem (making roads safer), they would simply design the roads differently. Speed bumps are also a very bad solution. Good solutions are "road islands" [1], "curvy roads" [2] or "metal rods" [3].
No limits on the highway either, except to mark more dangerous parts of the road (i.e. it's a suggestion not a limit).
By definition, if you don't crash, your speed was OK. So maybe there should be speeding-related fines only if you do crash.
> By definition, if you don't crash, your speed was OK.
Definition of what? By this logic SBF shouldn't be jailed but rather given an award for making FTX users whole with modest interest.
The law must scale to all of society. There cannot be different rules based on whether you are lucky, "skilled", or not. Most people overestimate the their competence, as evidenced by fatalities involving motor vehicles. (A professional truck driver I knew died, killing his wife, and harming his nephew just driving back home.)
Not driving cars at all offers the lowest. There has to be a degree of nuance when evaluating this.
Ironically in my town, we did have a "string" (3 people in 5 years) of pedestrian fatalities. All of which took place downtown where people actually do drive 25.
Well its not a sure rule of thumb that lower speeds are safer. People die falling bad from standing too. But it sure as hell makes it a guarantee you kill someone if you hit them at that speed. Especially some of these newer suvs where the front end is effectively a wall at pedestrian height.
I live in Texas and I would unironically feel safer driving the normal ~10-15mph above the speed limit that traffic is normally going than go exactly the speed limit, because I don't want everyone else flying around me recklessly because they all know that nobody goes exactly the legal limit here.
Yes! Speed difference is dangerous. So yes the difference in speed between vehicle and stationary objects it can hit (trees, poles, parker cars). On highways without a divider the danger is from incoming cars as that will double the impact speed. On highways with dividers having speed different from cars around you can be dangerous because it means either you are changing lanes to pass often else others are changing lanes often to get around you.
Laws are necessarily very blunt things. The actual optimal speed limit will vary with car, driver, traffic, weather, time of day etc, would vary hugely along the road and wouldn't be in neat 5mph increments.
But making such dynamic limits would be an extremely expensive endeavour.
If you want to optimize for least deaths and injuries, thr optimal speed limit is 0 km/h. Everything else is a tradeoff between convenience and potential harm.
> Speed is the most dangerous aspect of motor vehicles
Speed difference is dangerous. So yes the difference in speed between vehicle and stationary objects it can hit (trees, poles, parker cars). On highways without a divider the danger is from incoming cars as that will double the impact speed. On highways with dividers having speed different from cars around you can be dangerous because it means you are changing lanes often else others are changing lanes to get around you.
> Speed is the most dangerous aspect of motor vehicles
Not in the way you think. If you're going 55 because it's the speed limit, but everyone else is going 70, you're the most likely driver to cause a collision. https://en.wikipedia.org/wiki/Solomon_curve
Let's assume people are going at a speed that the road is designed to handle, since that's usually the case. In that situation, the behavior you're calling out as unsafe is simply "going faster". Now, in a technical sense that's true, but it's always true. Going faster reduces safety when you're above the speed limit. Going faster reduces safety when you're at the speed limit. Going faster reduces safety when you're below the speed limit.
If you reduce safety to black and white, then you should always go slower, until you're barely moving. If the speed limit is 40, that doesn't magically make it safe to go 40.
Black and white thinking leads to a bad conclusion, so let's add nuance back in. Speed is dangerous but roads are designed to let you go a certain speed while minimizing the danger. You're not being dangerous until you go over that speed. And that speed is almost always higher than the speed limit, especially in good weather.
Going over the speed limit is not itself a problem. It's going over the design speed of the road that's a problem.
> Let's assume people are going at a speed that the road is designed to handle
Let's not, because most of the speeding I see is from people who very mistakenly think they know what speed the road's designed to handle, because they don't give a crap about pedestrians, bicyclists, visibility, other vehicles, or really, anything but getting to the next red light faster.
Perhaps you drive in a utopia that's solely populated by traffic architects, but here in the real world, it's populated by normal people, many of whom are bad drivers, and bad judges of road safety, but are really good at hitting the gas.
Overbuilt roads aka “strodes”are real common in North America and as people tend to drive the speed they feel is correct not the limit it leads people to going faster and create unsafe situation. There’s a great not just bikes video on this iirc
A sign doesn’t really change behaviour but narrowing roads , separated bike lanes, pedestrian controlled crossings, roundabouts, and generally making the road “feel slower” does
Kinetic energy is proportional to square of velocity. It doesn't take large speed reduction to halve energies involved and thus the danger. Even not taking into account how crappy human perception and reflexes are.
I'm quite confused why I keep seeing posts like this downvoted in this thread. This post is nuanced and probably novel to most readers. Even seems correct to me.
There's a correlation between the speed limit and the design speed, but there's also a lot of mismatch and the bias usually goes in a specific direction.
A few mph over the speed limit in dry weather is rarely outside the design.
And I think I have a reasonable amount of nuance. If you don't have nuance you get "the sign can't be wrong" or "always go slower". The former is objectively not true, and I've never seen anyone seriously advocate for the latter.
The type of people who see a "lane ends ahead" and immediately merge, blocking up traffic and wasting a half mile of empty lane. "I'm in my assigned place and I did what I was supposed to!!"
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.
In my experience what causes the slowdown are the people who merged too early who then resentfully close the gap in front of them when people try to merge later than them, simultaneously increasing the likelihood that they’ll rear end the car in front of them and making it harder for the people trying to merge properly to do so.
Just use the lane normally and zipper merge when the lane ends. Don't waste space. Don't block people. You don't get brownie points for being in the "correct" lane as soon as possible, and it doesn't help to police others who are using the existing lane. It really isn't that hard.
A zipper merge is fine, both lanes tend to fill up.
What I often see if a lane that intended to go through and a turning lane that is backed up; people pretend to be on through lane, then stop to merge at last minute into long turning lane and void the line.
Regardless, Waymo is under the spotlight and they can't risk the regulatory hit of openly breaking laws, even if it's a perfectly normal thing for a human to do.
Indeed. Much as buying a smaller car makes you a hazard to everyone nearby because they cannot see you as easily. The most sensible thing for everyone is ever larger and more heavily armored vehicles. Won't someone think of the children. `/s`
All that said. If you cannot maneuver safely around drivers going the speed limit then they are not the problem.
Not really. Because speed works in relative. I.e. if everyone drives at 200mph it is much safer than if half drive 100mph and other half drives 200mph. Granted you can't have things appearing at 200mph.
Speed is not the problem deceleration is. Which happens more often when some percent of people drives slower than others.
Decreasing speed limits has the counterintuitive effect of increasing vehicle to vehicle accidents, and intuitive effect of increasing ticket fees. Pedestrian safety isn't that imprcted since a portion of drivers drives above limit anyway.
Probably 100% safer too
Speed is the most dangerous aspect of motor vehicles