Sunday, 12 April 2015

Authoritarian Madness


Have they ever thought that the bloody limits might be too low?  The responsible 'man on the spot' will always know more than the remote bureaucrat; be more informed about the actual circumstances prevailing at the time.

I recently drove from Ipswich, down the A12 around the M25 anticlockwise and onto the M3 then A303 to get to Thruxton. And back the day after.  The whole exercise was made more unsafe for me by either mass bunching of vehicles terrified of the 'grey' cameras, or just trying to keep within the indicated speed limit by constantly checking my speedo. If you drive under the speed limit you get in amongst all the heavy vehicles with drivers sitting with their pedal to the metal using their governors to  stick at 56 / 60 ish.

There clearly is a place for advice on speed - where road alignments make it impossible for drivers to know the circumstances; around live roadworks; as advance warning of an 'incident', for example.

Similarly many speed limits are 'too high'.  In my town there are lots of narrow cross streets with cars parked on both sides where to do  more than 20 is dodgy, yet the 'limit' is 30.  I cannot recall any news story of any incident in such streets.

But clearly what we have now is just persecution to satisfy the small minds of a small clique of authoritarian police and 'planners'.


As an ex-highway engineer, I know that there is a good case for lowering - or recommending - lower speeds in periods of high demand on, at that instant, under-capacity roads.  It is a proven fact that more traffic will get through any stretch of road under those circumstances as it can bunch up safely. But this does not need to be policed by cameras, especially if you explain to drivers what is happening and why.  It's all about trust.

This fact is also useful when we think about self driving cars. Such vehicles will be able to safely 'platoon' (in the jargon).  Which in turn leads eventually to the argument as to why HS2 should be killed stone dead.


The Stigler said...

The unsafe speed limit on motorways is going either 20% slower or faster than the rest of the traffic.

Which is safer? Driving while tired in a Morris Minor at 65 on a wet day in heavy traffic, or driving at 90 in a Mondeo when alert on a clear, Sunday morning with no traffic around? Which does the speed camera think is safer?

Swindon scrapped its speed cameras and it made no difference to road safety (the numbers actually went down although that's down to statistical variation).

Mark Wadsworth said...

Agreed, also to what TS says.

Lola said...

TS Or, 150 mph in Mclaren between motorway junctions on a clear moonlit summer night with no other traffic in sight, is clearly not 'unsafe'. Assuming the driver is at least half way competent, which I grant, many of the rich idiots that buy McLarens, aren't (FWIIW I know quite a few rich men who are entirely competent to drive at that speed)

The Stigler said...

Incidentally, I was having a thought as I drove home the other day that people's perspectives on cars often mirror their perspectives on the state.

There's very little control on roads - some traffic lights in a few places - but mostly people can just do what they like, and with that we only get 60 deaths per billion miles travelled. Roads are so insanely safe, mostly down to improvements in cars, that it's a problem that's hardly worth bothering with. You'd do better throwing all the resources of road safety at healthcare.

Lola said...

TS. Yes. That was the point I decided not to make at the speed awareness course I went on some months ago. (The course was total bullshit.)
But, roads are also insanely safe because the vast majority of people are responsible and should have been taught to treat every other driver as a bloody idiot (as I was). In other words people, when not being ordered about, are naturally responsible and do not need 'governing', which is bad news for all authoritarians. All you need are some very simple 'rules of the road' which generally have developed over time without much official interference. Markets working again.

Bayard said...

Lola, yes, but you are up against the "If it saves one life then it's worth it" brigade.

With all the cameras and what have you on motorways nowadays, it should be easy to switch from a speed limit to a "distance between vehicles" limit. If that was done, then pretty soon cars would be being manufactured with proximity indicators which tell you when you are too close to the vehicle in front.

Mark Wadsworth said...

B, good point. They don't really mention this in the UK, but when you do a driving licence in Germany one thing they drum into you is "leave at least two seconds between you and the car in front" which is a good rule of thumb at most speeds.

Lysistrata said...

@Bayard, Mark - absolutely.

Tailgating, which is variable depending on relative speed, is one of the worst habits of drivers who think they're clever.

It not only doesn't allow enough time to slow down, it decreases the forward field of vision and increases the number of times people touch their brakes which can lead to bunching several miles behind. I'm pretty certain this was taught even when I first learnt to drive decades ago.

Now, if only someone other than me could tell my husband that, he might take notice...

Lola said...

Agreed on tailgating. V Bad idea. And I know of what I speak as I race cars and in that environment 'tailgating' is de riguer...

Dinero said...

It has also been demonstrated that the case of one single driver leaving a gap between themselves and the car in front, thus driving at lower than maximum possible speed, and thus constant speed, can prevent tailbacks from occurring behind it, as that one car at constant speed stops the other drivers behind from having a reason to engage in the speeding up and slowing down style of driving.
In a certain type of traffic jam it is the speeding up and slowing down to close up gaps that causes tailbacks. The oscillation in speed can build up untill there is almost a standstill at the lower end of the oscillation.

Lola said...

D. Correct. The trick to driving efficiently is not to stop/use the brakes if you can avoid it. (FWIW Fangio was once asked how he could lap so much faster than anyone else. "More accelerator, less brake", was his reply. It's the same principle.) Leaving a good gap to the vehicle in front allows you to moderate your speed without using the brakes.

However if used properly the outside overtaking lane on motorways is exactly for that. It enables us to drive at different speeds and not hold each other up, so those of us who, for whatever reason, wish to progress faster than others, can.

Final question. Do we actually need speed limits?

Bayard said...

Having, like you, been sent for re-education, I learnt that the roads where there are most accidents are the ones where there are effectively no speed limits: country lanes. 60mph is too fast for safety in all but a minority of places, so drivers are nearly always constrained only by their perception of what is a safe speed to drive, which seems to be a little higher than it should be.

Lola said...

B It's the other way about. The facts are that M ways and trunk roads are 'engineered' and hence have safe alignments, sight lines etc. Whereas every other road is an 'evolved' road. If you think that most of these started as paths or cart tracks where the speeds were about 4 to 6 MPH max, then it is quite clear that doing any more than that could be unsafe. That's what traffic signs are for. To inform and warn drivers of hazards that they are unable to assess other than at walking pace. Speed 'limits' are actually speed information or advice. They have only become rules because the police can only operate on 'rules' as they are effectively bureaucrats with lots of power which need constraining.

Bayard said...

Lola, I'd dispute that: because of risk compensation, roads that are engineered and look "safe" are no more safe than roads which have evolved and look "dangerous". If a road is "improved" by removing blind corners etc. all that happens is that drivers drive faster as they can see better and for far too many idiots, that "faster" is too fast.

Lola said...

B. I was comparing M Ways and dual carriageways with non-'engineered evolved single carriageway roads.

Agreed that when alignments on existing single carriageway roads are improved in isolation hazard can be increased. You might trade safety for drivers (removing a huge tree in the outside of a bend) for extra perceived hazard for other people by effectively increasing safe speeds. That effect is well known.

At the same time you can (and I have) design and build single carriageway roads that are as safe as dual carriageway roads. Recognising that single carriageway roads will always be more hazardous then duel carriageway roads.

But accidents are still less frequent on improved sections of evolved roads.

Dan said...

What would appear to be going on is that the driving public at large are indirectly telling the police that the speed limits are set far too low. This is not just conjecture; there is actual real-world evidence of this.

In 1999, through legislative incompetence, there were no enforcible daytime speed limits on the motorway-class roads of the US state of Montana. By 2000, the safety lobby had re-established a 75 mph limit.

During the no-limit period, road deaths fell to an all-time low of 2.2 per month. When the limits were re-established, this more than doubled to 4.4. Interestingly the average speeds of motorists didn't vary much over this entire period; people didn't drive unsafely or much faster during the no-limits period, they simply seemed to drive a lot more safely.

This is evidence that is never discussed in public by the usual road safety crowd.

Another body of evidence that isn't discussed is the data gathered by Idris Frances on the effects of speed cameras on the motorists of London. He has gathered statistics on road deaths and injuries on roads which have fixed speed cameras on them, and those which do not and has found something interesting: roads in London are getting safer.

What must be rather galling for the police is that statistically speaking, the reduction is identical whether there is a speed camera on a road or not. Fixed speed cameras have no demonstrable effect whatsoever on the safety or otherwise of a road; clearly something is having an effect or the steady decrease in KSI accidents would not be evident, but it is not speed cameras.

Bayard said...

"What must be rather galling for the police..."

I doubt it, the police can be heartened by the knowledge that the fall in road deaths must be due to better active policing if the cameras are having no effect.