I don't know anything about USA, but my understanding of other humans tells me that "Waymo is 10-25% slower than the rest of traffic" actually means "Waymo drives at the legal speed limit for that location, without surpassing it".
Probably 100% safer too
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
All that said. If you cannot maneuver safely around drivers going the speed limit then they are not the problem.
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 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.
Our high death rates reflect this.
I drive in an area that has a lot of overbuilt roads, and I don't think that's a very uncommon situation.
> they don't give a crap about pedestrians, bicyclists, visibility, other vehicles, or really, anything but getting to the next red light faster
That's very dangerous even if you strictly follow the speed limit. It's a separate problem.
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
My point is that until the road is narrowed, the safe speed on it may be lower than the average backseat traffic architect might think.
Want to know what any arbitrary driver on a road has as a reference for “the design speed of the road”? The posted speed limit.
I’m not saying their argument is right or wrong, but just that this post isn’t nuanced or convincing.
There is a link there, that refers to lots of scientific research. From almost a century ago to almost today, and in a huge amount of agreement.
Do you have more nuance than that?
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.
Laws were put in place because people are not in fact qualified to make these assessments.
The only nuance here is that you are not required to go the speed limit at all, you can and should go only as fast as the conditions allow.
who gives a shit who is at fault when they're in an accident?
the goal is to avoid the event all together, not to have a scapegoat.
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.
You mean the people who must get past every single car and merge at the last possible second?
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.
Not sure why did you link it.
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.
Ignoring reality
A lot of people killed on the road
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!)
Don't we already have school zones which are 20mph when kids are around and higher otherwise?
If you want people to drive slower you just design the road to slow them down.
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.
[1] https://www.google.ch/maps/@46.9519887,8.6213984,3a,75y,174....
[2] https://www.google.ch/maps/@46.0665621,14.4965949,3a,75y,188...
[3] https://www.reddit.com/r/Damnthatsinteresting/comments/14vls...
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.)
Texas vs EU: https://i.redd.it/jlqp9vv8flb31.jpg
But making such dynamic limits would be an extremely expensive endeavour.
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.
If the maximum traffic density doesn't happen often, then people can understandably be annoyed when they can safely drive faster most of the time.
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.
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.
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.
I'm having a hard time understanding how that makes sense. I understand that matching the flow of traffic is important, but more important than the speed limit? They're there for a reason.
If the speed limit is 30km/h and everyone is driving in 50km/h, you're saying you'll opt for driving at 50km/h?
Besides, if there is multiple lanes, you take the right lane and follow the speed limit. The ones who don't want to adhere to the speed limit, have the left lane(s).
And in the case of it only being one lane, you can literally decide the flow of traffic by adhering to the speed limit, and everyone behind you need to follow it, and once it stabilizes, that's now the flow of traffic, problem solved?
(Just as a disclaimer, I do sometimes drive above the limits myself, but limited only to the highways, never on road with a limit below 120km/h)
Here in Vic (the next state over), people think that law is stupid because it’s apparently less safe having everyone on a freeway driving at different speeds. It makes changing lanes much more difficult and dangerous. Here learner drivers are expected and encouraged to match the speed of traffic (obviously obeying speed signs too).
I suspect vic is right on this one. It probably is more dangerous having different drivers driving at different speeds. At least, more dangerous to human drivers. But what do you expect Google to do about it? Make their entire fleet break the road rules? Their licence to drive their cars on the roads at all is on a trial basis. They’re being closely watched by everyone. Even if it’s potentially unsafe for other drivers who are speeding, sticking to the letter of the law is really the only choice they have here. Maybe in time all traffic will flow at the posted speed. And officials will finally feel comfortable raising the speed limit to match the speed everyone actually comfortably drives at on the roads.
The consensus from the folks writing laws appears to be that the problem is not in fact solved in that case. There are laws which apply independent of your speed that require you to give way when more than X number of cars are behind you constrained by your speed (X varies by jurisdiction).
Of course the response to this is usually "but if I am going the speed limit that other law cannot apply." Very much like the laws saying you must keep right unless passing someone. Everyone seems to have their own opinion on which laws they will follow, and which they can ignore.
Yes absolutely. Speed limits are cooked up in a room somewhere and do not reflect the actual conditions of the road. The real world situation you find yourself in when on the road is too dynamic to suggest a number on a sign should be the ultimate authority
It's very understood that when it's raining or snowing or foggy you should slow down because you drive to the conditions of the road because that's safest.
If everyone around you is speeding then that's also a condition of the road, which you need to adapt to
I think theres a bit of nuance. If the flow of traffic was all being crazy lunatics then yes I'd say so. But I would feel safer without other cars flying past me/around me because I decide to go 70mph when everyone else around you is going 80-85.
Many believe the myth that as long as we’re going with the flow of traffic, we’re not doing anything wrong. It makes sense– everyone else is going the same speed, so why shouldn’t you? There’s no way a cop could pull you over if you’re just going with the speed of traffic. Wrong.
If you argue that you were just driving with the flow of traffic, then you are essentially admitting to speeding. Other people breaking the law does not justify you breaking the law.
Do they? Almost without exception the argument for going with the flow of traffic is that it is safer, not that it is the most legally defensible.
Apparently they even have entry and exit cameras on some freeways - and they take photos of everyone to check your average speed. Even if they don’t catch you in the act of speeding, if your average speed is over the limit they’ll still send you a fine.
The moral of the story: Don’t speed in Melbourne. It’s a meme that everyone who visits the state gets done at least once. Everyone in Sydney has a friend who’ll tell you the harrowing tale of their vacation speeding fines.
Roads can be designed to slow down traffic, but slapping a 25 mph speed limit sign up on an 80-100’ wide 4-lane road does not slow down traffic.
A road near me was reconfigured with a center turn lane and two lanes from four lanes and traffic slowed from 40 mph to 30 mph, the speed limit for this particular road.
https://www.strongtowns.org/journal/2021/8/6/the-key-to-slow...