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Comment by snvzz | Hacker News Reader

The acceleration you needed wasn't there the moment you needed it most, because your subscription expired or your car couldn't get online to check that it was still active.

And now you are dead.

Safety is now software, on a subscription model.

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“Driving too fast for conditions or in excess of posted speed limit” is the largest related factor in fatal crashes in the US, according to the NHTSA, it ranks above alcohol (by nearly 2x!). https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/...

Do keep in mind that we’re talking about a subscription to go 0-60 MPH in 5.2 seconds vs 0-60 in 6.2 seconds. The non-subscribed acceleration of 0-60 in 6.2 seconds for this specific car is far faster than the majority of cars on the road can accelerate. Do also keep in mind that the non-subscription features of the car must pass all safety standards, therefore safety is clearly not on a subscription model. There are plenty of valid reasons to dislike these auto-maker attempts at rent seeking, so let’s not be hyperbolic about them, lest we undermine the stronger arguments.

People who did not crash don't appear on statistic though (just making a point)

It's definitely harder to count the time spent speeding when that speeding doesn't end in a crash, but the NHTSA still tries to do it [0]. About 19% of vehicle miles are driven at more than 10 mph above the speed limit on highways, somewhat fewer on city streets.

[0] https://www.nhtsa.gov/sites/nhtsa.gov/files/documents/812485...

I'm talking about sudden acceleration to avoid danger, not constant speeding. Fast overtakes might rarely be registered because those are short lived.

That might seem like a logical point, but think about it a little more; if speeding is helping some people to not crash, then the point you’re effectively making is that speeding might actually make you even more than twice as likely to cause a fatal accident as a drunk driver, but sometimes helps enough that it evens out to be only twice as likely to cause a fatality.

It’s not true that non-crashes aren’t represented here- the NHTSA statistics capture the rate of crashes in terms like crashes per vehicle miles traveled, which represents both the probability of crashing and the probability of not crashing (one minus the probability of crashing). The fact that speeding is a huge factor in many crashes and that it increases the chance of death does in fact demonstrate that it’s overall less safe to speed. Speed might anecdotally help some people in some situations, but the actual stats do prove that the net effect of speeding is greater risk.

Acceleration != speed.

Acceleration increases the degree of control you have over your vehicle. That control could be the difference between life and death in an emergency. For example if you see a car driving towards you from the side (e.g. they're running a red light), increased acceleration could allow you to get out of the way in time.

More conventionally, increased acceleration allows you to complete an overtaking manoeuvre in a reduced time. Reduced overtaking distance is fairly universally regarded as also reducing the risk of an accident.

> Acceleration != speed

That’s true, good point. (But we’re talking about a sport feature of a Mercedes car with unnecessary amounts of acceleration.)

> Acceleration increases the degree of control you have over your vehicle

That’s not true. You’re exercising control by accelerating, but not increasing control. Braking and steering are also exercising control. Accelerating too fast in wet or dusty conditions reduces control. Accelerating too quickly when people around you don’t expect it increases the risk of accident.

> Reduced overtaking distance is fairly universally regarded as also reducing the risk of an accident.

I’ve never heard this before, can you back this claim up with some evidence? The NHTSA report I posted is quite thorough and does not mention passing time as a risk factor. I’m sure you’re right and it is true when overtaking into oncoming traffic, if you cross the median. I doubt this is true for separated freeways like most of the urban US interstates inside city boundaries. I’m sure your claim here is not true when people exceed the speed limit in order to overtake, which is a very common occurrence where I live. Much of the passing that goes on happens when someone overtakes another person who’s already traveling at or above the speed limit, by further exceeding the speed limit. This is not made safer by doing it faster.

Nobody ever died because he did not have enough acceleration.

That whole argument is as old and tired as it is wrong.

Escaping from dangerous situations is not a thing. Speed got you in that situation in the first place.

"Nobody ever"?

Wouldn't such a thing be useful when overtaking?

This is an SUV that can do 0 to 60 in 6.2. Those used to be sports car numbers not too long ago. 5.2 is ludicrous for anything without an electric motor. It is not as if this is a 90s Yugo.

Some car magazine a while back did a side-by-side comparison of two Mercedes sedans, one with a V6 and the other with a V8. They were happier with the V6, because nobody can use the extra power given speed enforcement on highways. So do yourself a favor and just don't pay for it.

I disagree. I am in a bad situation. I know my car. I either brake or accelerate to get out of this pickle. I choose to accelerate, based on what I know that the car can do, as that seems to be the safest. And it doesn't react the way I expect. Now I'm dead.

It seems highly unlikely. What maneuver are you pulling where you need to floor it and your 0-60 time comes into play? You see a boulder rolling down a hill toward the road a quarter mile away, and you say "I can beat it!"

Something unexpected is moving into your lane (wreck from the other lane, semi driver falling asleep, moose, ...), and you need to apply some combination of braking, accelerating, and turning to avoid it.

Less drastically but much more frequently, just when merging onto the freeway you'll typically choose to accelerate or brake based on what's most comfortable given the available traffic openings, and finding in hindsight that acceleration wasn't actually an option isn't going to make the road safer.

You would only find that if you were literally flooring it to merge. That's not safe regardless.

Have you really never been in a situation where you need to accelerate out of the way of another driver braking the law? For example, driving through an intersection and suddenly you notice someone is running their red light on a collision course. You must either go forward or backward. Much more difficult to reverse than to accelerate.

I check intersections before proceeding through them , so no that hasn't happened in 250,000 miles of driving.

And what is that, like 0.5 seconds to make a difference? How much further will the car be when it had this subscription vs not having the subscription?

Half a second seems roughly right. An exact answer depends on the car's power band and other more complicated factors. You'd expect an extra 2-8 inches, and if the interesection were a bit wider and slower so that you had 1.0 seconds you'd expect an extra 16-64 inches. Also, on such small timescales the engine's responsiveness would come into play, and it's unclear if the tuned package would affect that for sure, but it'd be hard for it not to.

2-8 inches probably won't give you better odds of any meaningful outcomes beyond an extra few percent. 16-64 inches could easily be the difference between a miss and a crash (especially if the red-light runner swerves or counting the selection bias in which distribution of possible strike zones you're likely to have predicated on the assumption that accelerating was a reasonable course of action), or would very likely be the difference between an extremely dangerous collision with the driver's door and something more reasonable toward the back of the car (worse with kids in the back -- thankfully for the purpose of this discussion, only 15% of cars in the US have passengers).

That depends how the UI to the extra power is implemented. I bet the lower power mode still has increasing power the further the pedal is pressed (as opposed to simply finding there is no extra power if you floor it -- a smooth monotonic graph rather than one clipped at the top), so you still have a feedback loop going through the latency of conscious thought as you press the pedal the "right" amount to accelerate (not flooring it), find that it's insufficient, and now still have to choose between braking and accelerating -- either braking after you've already decided that's the less safe option and accelerated enough that that's probably more true than it was previously, or accelerating now that you've wasted some time and need to accelerate more briskly than you previously would have (maybe even flooring it, which as you say is not a safe place to be) while also having doubts about whether attempting to accelerate faster will actually suffice since your current pedal input should have also sufficed.

Edit: Not to mention, lack of safety in an absolute sense doesn't mean that the safest option for a given driver (predicated on the assumption that it looked safe to go as far as the onramp and there's no way off other than merging eventually) wouldn't be to floor it to merge. In the Bay Area in particular, drivers are notoriously aggressive about both tailgating and blocking merge attempts, and faced with a tricky merge you might find that braking input is unlikely to work (no openings toward the rear), heavy braking to avoid the situation is unlikely to work (in theory you're supposed to yield to the freeway traffic, but doing so will probably result in the tailgater behind you rear-ending you), and the nearest available opening in front of you requires heavy acceleration. It'd be better if everyone could be polite and zipper merge, but in a bad situation with limited personal control you can only hope to make the best of it.

You do a legally allowed right turn on red. But visibility to the left is bad, and only as you turn do you notice a bus on your left. You floor it to avoid the collision.

To be fair, a vehicle that does 0-60 in 10s can probably pull this off too.

That's bad driving, sorry. If you don't have good visibility, just don't turn right on red. It's a stupid law that allows it anyway and if makes streets more dangerous to pedestrians.

I agree with you. But such turns are not at all rare and acceleration still improves your safety if you find yourself in that situation.

What about all the other situations where s celebration contributes to danger?

There's a trade-off but there's nothing to say that the optimum is to follow Mercedes's or Tesla's solutions to their profit maximization problems.

Obviously... that Star Wars screen where they just dropped there bomb in the through regulator vent and need to Get Out Real Quick before the Death Star explodes.

I agree with the "speed is not the solution" point of view. But if you're used to your car behaving in a certain way (accelerating fast in this case) and then your subscription expires and suddenly, while overtaking someone, you realise that it's no longer behaving the same way. That could be dangerous.

Muscle memory is everything when driving

Due to my car having good acceleration I spend less time on the opposite lane during overtaking. This is safer for those in my car, the vehicle/object I'm overtaking and the traffic from the other direction.

It's a win-win-win all round.

Why is it safer? Are you saying that you would otherwise overtake another car in an unsafe way, perhaps when you haven't enough visibility to check if there is no oncoming traffic for the overtake time? That's on you. The decision is the same, in a fast car or a slow one.

A faster car allows you to safely overtake more frequently than a slow one because it requires less time (distance) to complete the accelerate/overtake/return operation.

Many drivers in slow cars think they can execute the same manoeuvre as the fast car in front of them and this is when accidents happen - often fatal too.

So bad driving causes crashes? Who would that thought? It's not that the faster car is safer then, it's just the fact that if you try to overtake without sufficient room, you will be taking a risk.

No-one is disputing that a faster car allows you to overtake faster.

Honestly you should not be overtaking in the other lane at all. It's a large risk to you and the other drivers on the road, and all you get in return is a few seconds off your trip.

This assumes the driver in the front is a good driver. What if the driver is constantly breaking and accelerating? Or the driver is simply a big truck that cover the view

I take your point, but if the driver in front is a "big truck that cover the view," then that is all the more reason not to pull into the other lane! This is probably the most dangerous time to attempt this sort of merge.

>What if the driver is constantly breaking and accelerating?

I've found that there are two general strategies that work well in this situation.

- Simply increase distance and wait longer to catch up to the driver in front of you. This accounts for their bad driving.

- Modulate your speed using the car in front of the car in front of you. ie, focus on the 2nd car in front of you. They're likely driving with the flow of traffic properly and won't constantly be accelerating and braking. It might sound unintuitive to focus focus on a car other than the one in front of you, but this can actually be more safe: You've made enough space between yourself and the car in front you to avoid an accident, and you're better prepared for when the actual braking will occur.

I mean, sure, but it's stressful. Maybe I have a 3 hours trip in front of me, I don't feel comfortable having a bad driver in the front.

The big truck example, I wasn't suggesting you overtake without view, rather increase the distance, then overtake.

In Italy you can overtake ONLY on the left, so it's not out of the blue to change lane just to overtake.

Just do it safely.

In the end nothing stops you from getting out of the highway, wait 10 minutes and resume, to be done with all of this.

If people should always treat yellow dashed lines as yellow solid lines, then why do we have the former?

In the UK the overtaking driver is expected to give ample room and the example diagrams on this highway code guide [0](considered to be a good resource) implies the driver occupies the opposite lane.

Here in Ireland the highway code is almost identical given the history of British influence [1].

Giving 1.5-2m distance would imply use of the opposite lane.

[0] https://highwaycode.org.uk/overtaking/

[1] https://countrysideallianceireland.org/latest-news/changes-t...

Or, Due to your car having good acceleration, you make worse choices about when to overtake and increase your odds of a head on collision

On the contrary, aside from a passport, my driving license is the most valuable thing I own and will stay within the law to retain it.

There's still a range of choices on the safe <-> dangerous driving spectrum which fall within the law.

Merging on to freeways? Turning in to traffic? Passing a slow car in fast traffic?

I spent years driving a $500 shit box car. There are loads of situations where acceleration mitigates other people's mistakes. I lost that car getting rear ended - not my fault, but it could have been avoided with more power (saving myself weeks of neck pain).

So you're driving in a manner that if your car gets a hiccough and underperforms, you're in extreme danger? That happens all the time with ICE cars...how are you not dead yet?

In a manual car you drop the gear.

Yes, which you don't hit 100% of the time.

The only car I ever had that problem in was a Porsche 964 Carrera RS track car.

Yes but imagine you're in a stressful situation where your life is in danger because you didn't realize your subscription expired and your 0-60 is 6.1s instead of 5.1s.

Are you hitting doenshifts 100% in those situations?

You aren't because it's an automatic gearbox.

If in doubt, flat out.

I was traveling and rented an underpowered hybrid ford something that defaults to Eco mode every time you turn it on. I was waiting to turn left in crosstraffic and when I saw my chance hit the gas to go and I assure you I almost died due to lack of acceleration.

On a motorcycle, reaction speed is all you have to save your ass and accelerating away from danger is a totally valid strategy in many situations. A car may not be able to squeeze ahead as easily in a bind because of its size but having enough reserve power still makes some maneuvers safer (e.g. overtaking a slow vehicle).

The “speed is safety” bit is probably a lot more obvious to motorcyclists but applies to everyone on the road, even if the situations are less likely. Imagine some road eager tries to pit maneuver you but you’re able to accelerate away and they miss. Or you’re not able, and you end up dead.

I hope the people who designed/developed do not have clean consciouses.

Totally. What are they going to do next, put your banana dropper on a subscription? So next time some road rager fires a turtle shell at you it doesn’t harmlessly hit your bananas, and you end up dead.

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