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If you think highway driving requires hard braking, you're a bad driver.

If you think people are going to cut in front of you, provide a safety cushion large enough to account for that. Aggressive drivers almost universally will consume the forward part of the space cushion you leave. At most you will simply need to lift the accelerator to maintain space. The only time someone cutting in front of you should require hard braking is if they also brake hard.

It does require patience to do this, because all aggressive drivers will use the space you provide. But ultimately the travel time difference in flowing traffic is negligible.

I'm one of the faster drivers and I maintain a safe distance. (I usually have the most distance in rush hour.) It's very easy with adaptive cruise control or the other self-driving technologies that are on the market.

The only people who cut too close to me are driving recklessly.

That being said: If you're in the mode where people are constantly changing lanes in front of you, think a bit about how you're driving: On the freeway you're supposed to stay to the right except to pass, and you're expected to keep up with the flow of traffic. Are you going slow in the left lane? Are you driving too slow? Are you camping in the right lane by a busy interchange?

This is accurate in many ways. I use the auto cruise feature on my car frequently and I notice several things happen unless I set the distance as close as possible (which I don’t like to do. ).

1. In any amount of traffic above “a few cars” people will cut in front of me, sometimes two, negating the safe following distance. Regardless of speed.

2. If I have a safe following distance while waiting for someone to get over. (I e they’re going 60, I want to go 70), if I have my distance set at a safe following distance, people are much more likely to weave / pass on the right. (My theory would be that the distance I’m behind the person in front of them signals that I’m not going to accelerate / pass when the person gets over ).

Disclaimer: I don’t usually have to drive in any significant traffic, and when I do (Philly, New York City), I’m probably less likely to use the automatic features because the appropriate follow distance seems to increase the rage of drivers around me.

Tailgating is against the law. Tailgating causes hard braking.

I recently pulled my travel trailer from OK to Charleston, SC and back. I never drive over 65 MPH for safety and MPG reasons. I always stay in the right hand, slow lane except if I have to take a left lane exit. Since I was always driving slower then everyone else, not once did I have to hard brake. Tailgating is a choice and a dangerous one.

I was never honked at, even by the crazy semi truck drivers.

> North America

Having driven all over NA, and Europe, I find it more prevalent in NA. Less distance, more people in large pickups throwing their weight around to make someone move out of the way.

And a design of giant freeway interchanges that require shifting lanes.

E.g. on the 405 in CA. 7 lines going South from the Valley towards Santa Monica.

That's 7 lanes you need to cross if you're in the HOV lane.

Does it really matter though? Is the end result just a couple of minutes later in a 30 minute commute? Or does it actually make a large difference in travel time?

Okay I'm thinking of a very Shenzen kind of gizmo for your car that projects a bright red laser "keep out" box on the road in front of your car which is adjusted in size for your current speed.

I live in a place that has harsh winter conditions with ice, gravel and the occasional loose tire stud flying into people's windshields, warranting frequent expensive replacements.

Somebody on the radio said that "just set the adaptive cruise control to max distance and your windshield will last way longer". It does feel overprotective at times, especially in slow and dense traffic, but I think there's a nice point in general.

I find it quite easy to hold/manage a tight space that people won't cut into, and don't have to brake hard, because I look ahead.

To be sure, it's more mentally taxing to hold a tight gap, so it's not something you want to do all the time, but it's fine.

False. I've done it many times - when you open up space two cars jump in, but the rest don't and so the space remains. But you notice those two cars and think it means more than it does.

Why does this require "hard" braking? If another car cuts in front of you just decelerate gently. You don't brake and wait until the gap is big enough (also if this is stop-and-go traffic, you should be trying to avoid braking at all)

The most frustrated people are those behind you, and if I was id soon be another person merging in front of you. If people are constantly merging in front of you, either everyone is going too fast or you are going too slow :)

I had a somewhat similar experience - as I recall, most beeps happened as a result of a few stop lights with too-short yellows (e.g. the light changes yellow and you, even though you are below the speed limit, either panic stop or run the red light)

The only possible fix as a driver was to try to develop an intuition for spotting “stale” greens and start slowing down despite the green, anticipating the yellow.

I feel at least partially vindicated by the fact the lights in question eventually had their yellows extended.

If there's no extra exit lane, the right choice is to slow down traffic on the highway.

What will happen if there's some oil spill or brake failure at the point you think you should break hard?

Just like Lightning McQueen: https://www.youtube.com/watch?v=AvhFjVj7k44

My Cupra Born does this; it has a little line that it draws on a "road" with the car in front, and you have to put the car in front of the line to be safe. Its quite a fun little system haha, works well on me!

My wife's VW will show the following distance and if you are too close a small icon is displayed on the dash. I believe its warning you that if there is emergency breaking required for the car it will not be able to stop in time.

It also shows how close you are to the car Infront in "car length" units with a nice big indicator and the adaptive cruse control will follow that distance mostly on its own between 30-100mph

One of the few things I really don't like about my Subbie is that it tries to help braking.

I'm all in for traction control and to some extent ABS, but braking hard and upsetting the car's balance when you don't need it is dangerous.

A lot of them do. My wife's VW beeps an alert if you're too close to the car ahead of you. It might be that it only activates above a certain speed.

I think it will also back down the cruise control (if set) if it detects that you are gaining on the car ahead. That might be MILs Toyota though.

I learned the "two second rule" in Driver's Education 45 years ago and generally follow that. Nothing more annoying than having the car behind you riding your bumper.

> Why hasn't gamification of safe driving habits been built directly into the car itself before now?

I am so glad it hasn't. Data point of one, but gamification now has the opposite effect on me: it's such a well-worn pattern that it just annoys me. It was great when it was novel. I wonder how many others feel the same but without sampling it's hard to know.

Back when I had a Prius, I made a conscious effort to avoid using the brake pedal during the highway portion of my commute. It made a small difference to fuel economy, but treating it as a game reduced the frustration with stop&go traffic.

I don't think it's marginal since accelerating the car needs way more energy than fighting loses due to wind and tyre resistance.

Also, a bad driver mis-breaking trips the cars behind into breaking too, which multiplies the energy waste and may also cause accidents through fatigue.

Mare experienced drivers will give you more leeway to avoid tapping the brakes with you, or simply go for a staring overtake.

The balance between safe following distance and letting people cut in varies a lot by city. Maybe he learnt to drive elsewhere?

I remember being too aggressive when I got to the Bay Area, and learning how nice it was to be let into the lane I needed to avoid being forced on a 5mi U-turn. When visiting back home I was too nice and people told me so.

I've reached a balance. Aggressive enough not to be taken advantage of, but being nice to drivers in need, specially when it doesn't really change things for me, like when letting a driver in costs me nothing because of how bad traffic is.

It is called the zipper merge. You were in the wrong for waiting in the stophed lane and the other person right for passing all you thinking you are better.

A cousin of mine is abysmal to drive with as a passenger. He follows too closely to the car in front of him, regardless of lane / speed. He will slow down, follow closely, and then aggressively pass. Repeating ad nauseam.

No smooth maintaining of speed and nice passes as able without slowing down.

Surprisingly, his accidents have mostly seemed to involve gas pumps, barriers, and other obstacles at low speed.

Only two, then people who maintain their lane are there and there is space.

They point in opposite directions because they’re not measuring the same things.

Google is measuring where on the road most hard braking events happen.

Insurers measure who is having the most hard braking events.

(Though for an insurer, it’s the same thing - whether you’re risky because you’re a bad driver or because you drive on poorly constructed roads or around other poor drivers is inconsequential to them)

Some road designs are risky because they encourage risky behavior. And "risky" is relative. A good driver should recognize risky road segments and drive even more defensively than normally.

A driver who frequents risky roads is a concern to insurers, just as a driver who has risky behaviors.

The cause of hard braking isn’t mutually exclusive: bad driving or bad road design.

Driving on bad roads is just as bad for insurance as a bad driver is.

Some amount of that is inevitable, but there is another level of defensive driving where you anticipate poor behavior and arrange that it won't cause an accident.

Have a look at a few dash cam accident videos [1]. There are many maladaptive patterns of behavior, but a frequent one that the average good driver can improve on is limiting speed on two occasions: when approaching a blind spot, and when passing stopped or slow traffic.

That second one gets lots of otherwise good drivers. They seem to think that by limiting their speed vs slow/stopped traffic they'd be encouraging people to dart in front of them. Which is somewhat true. But with limited speed, that's an avoidable or less injurious accident. By gunning it past stopped traffic, you make the accident unavoidable and more serious.

[1] https://www.youtube.com/@IdiotsInCars1

If you take a seasoned motorcycle rider and put them in one of those dashcam subs, they'll rip their hair out.

Most people have near zero defensive driving skill, and view someone pulling out in front of them as "nothing I could have done", when the dashcam shows the offending driver showed 5 signs of pulling out ages before the accident occurred.

Drivers often believe that their insurance rates should be based solely on whether they follow driving rules, but the risks to insurance are not isolated to this. Someone can follow every rule perfectly, but if they are involved in an accident they incur costs for their insurance company.

I hate the warning myself and I use the app the parent is from. I also suspect I am an outlier in not having an accident in 20 years.

It’s this obnoxious audio warning that tells me I had a hard breaking and it’s 9/10 because I stopped at a red light that I would not have made on yellow. And then it sends me tips and reminders about reducing hard breaking events and it’s annoying. I know they have done the analysis but it detects moderate hard breaking which is frustrating. One of those things that I am sure in net is positive but perhaps slices of the population it does not benefit.

When people learn to do things by reacting to inputs, they learn much better when the input comes soon after the action/inaction they are trying to train, rather than long after. When you can tie specific acts as a driver to a later financial penalty it helps you learn to avoid the specific acts, otherwise you'd stuck having to figure out in three weeks when the bill comes around what you were doing on the date the insurance statement flagged as a hard stop.

Yep. We work with CMT and we’ve both done extensive testing on this. I think that often people don’t necessarily know what a hard braking event actually means, or how it’s quantified. Giving that realtime feedback helps close that gap in understanding

Anecdotally: I leave the fuel efficiency display as the instrument cluster display on the hybrid that I drive and it significantly changes both my acceleration and braking behavior.

There is a minor financial aspect (price of fuel), but I’m far more interested in seeing if I can get a better “green score” at the end of the drive.

Does it matter why? The important part is getting people to change behavior.

of course if they change such that they don't break hard when needed that is bad, but if the change such that they don't need to break hard in the first place because they slow down in places that are dangerious that is the point.

Regardless of everything else, forward collisions are most likely to have the driver considered at-fault. Seems like reducing those in your insured population would reduce covered losses more than reducing collisions where your insured may not be at fault.

Have you used one of these apps before? They capture a lot more than emergency stops, what I would classify as the above normal brake effort but not hard braking. Im sure the data exist to set the cutoff but its a lot more than “jam your foot on the pedal braking”.

It’s still out of the norm braking for my style of driver but from what I see on the road, people drive aggressively like this. Especially in the US.

Obviously people know, but theres no impulse to introspect on why or how. Knowing that someone else knows you had a hard braking event taps in to our social brains to provide a much stronger response to the event. When we know people are watching we're more likely to try and justify our behaviour.

A lot of people don’t realize that what they consider normal driving is actually aggressive driving by other metrics

Because their definition of hard is not a slam on the pedal braking. It’s definitely out of the normal stopping but it’s not as hard as you might imagine. I could easily see people not realizing this.

yeah the interesting part is that the carriers already have most of this data from telematics apps, it's just sitting in corporate silos.

if we could bridge that gap, the economic incentive for municipalities would be massive lower accident rates mean less property damage and fewer expensive liability lawsuits for the city. it's basically a potential safety feedback loop that just needs the right data sharing protocol to actually kick in.

i'd love to see a safety heatmap layer, but the legal hurdles are probably massive. the second google puts a high risk badge on a specific road segment they open themselves up to lawsuits from local businesses or property owners claiming the algorithm is nuking their traffic or property value. it's probably going to stay in the hands of traffic engineers and underwriters for a long time.

Google is offering this as part of the geospatial platform that they market to governments for huge $$$ so I don't think you are going to get it for free any time soon. Maybe limited access if you have an Earth Engine developer account?

Yeah, Google and Apple do probably have much more first-party probe data of passenger vehicles. But it really depends on the type of traffic data product. For some use-cases, it's more than sufficient for the vendor to buy probe data from specific types of fleet vehicles (like work trucks).

Where Google/Apple's coverage is quite valuable is for near-real-time speeds for atypical events -- say like yesterday's Super Bowl. But that's not what this blog post is about -- this post is about a well-established pattern that can be identified with historical datasets.

All that to say that vendors sell a wide variety of data products to transportation planners, but just because Google is now entering this niche market doesn't mean they'll be "the best" or even realize what their strengths are.

It does look much more like a revenue play. The data already exists, but not from the conglomorates and not as uniformly formatted.

Why can't Gooapple suggest this today?