Yet surpising how infrequently you see the 20mph being adhered to. These people, already travelling very short distances, must be saving at least 30 seconds a year?
20/35 is 4/7 the speed, and therefore it makes every trip take 7/4 as long. So you spend an additional 15 minutes on every 20-minute journey. You're rapidly going to waste more human lifetimes sitting in cars than you would ever save from driving slower.
The number of people who justify driving as fast as possible to "save time" and then waste lots of time on other pointless activities is quite incredible. It's almost as if they're not really concerned about time at all...
First, the existence of hypocrites and irrational people is not a counterargument to appeals for efficiency.
Second, those pointless activities are what we're saving time for. I want to get more work done, and retire sooner, just so that I have more time for my pointless activities. People who don't begrudge every minute they spend in a car, in my view, are failing to maximize the leisure time that should be their chief goal in life.
Until you can donate someone your time, that's not how it works. This take is "my 5 min is so important, I'm willing to risk someone's 60 years" (scaled to thousands of people).
You can also make other choices that reduce your 15min to begin with. (If the small difference there makes important changes in your life)
I don't need to donate them my time, they are also saving the same 15 minutes per trip. Do I also have to invent time donation to propose other time-savers like dishwashers?
> "my 5 min is so important, I'm willing to risk someone's 60 years" (scaled to thousands of people).
The scaling matters! Boston has 1.8 million drivers losing 150 hours in traffic per year, according to https://inrix.com/press-releases/2019-traffic-scorecard-us/. Imagine that all of that traffic was caused by our desire to save a single human baby. 270 million hours lost to save 700,000. Would you agree that's not worth it? That probably those 270 million hours would produce enough economic output to save a different baby instead?
To me, a 75% increase in travel time is high enough and 35 mph is slow enough that I think everyone's 15 minutes is, in fact, worth risking someone's 60 years, once every couple of years. I could be proved wrong about the math, but it seems to me it's mostly an argument about risk tolerance.
Correct, assuming a perfectly spherical car on a frictionless road with no other traffic, hazards, or traffic controls.
In the real world 20mph puts a cap on your top speed only in the few instances you could possibly go that fast. Factor in lights, queueing at rotaries, slowing for emerging traffic, slowing for and then going around cyclists... ad nauseam
It is measured though! City hall & TRL track this. In outer London the average traffic speed overall is about 20mph. In inner London it’s about 12 and 8 in the centre. I don’t think the 20mph limit makes a real difference to journey times, but it does make the streets safer especially for people not in cars.
I wonder what is the effect on climate change? Are we killing the planet by doing this? Should we instead up the speeds to closer of where cars are most efficient? Also need to remember that each fatality is good for environment...
Around 45 mph is the most efficient speed for a car engine last I checked -- they always tell you to slow down to save gas, but never to speed up. I feel that shows their real agenda is more about limiting speed than efficiency.
It makes a lot of sense in terms of road safety as well as noise, and makes little to no difference to journey times.