The article by David Brooks on speed-recording signs (Monitor front page, July 12) unfortunately left out one important question: If 90% of drivers were going faster than the speed limit, were they driving unsafely or was the limit set too low? Unreasonably low speed limits not only waste drivers’ time and increase frustration, but probably waste fuel and contribute to climate change if they are low enough that drivers cannot use their highest gear.
At one time it was assumed that in the absence of hidden hazards or an abnormal crash record, most drivers would behave responsibly and the speed limit could be set based on actual observed speeds. You could for example use the 85th percentile speed, which would allow for 15 percent of drivers going too fast for safety and the rest being okay. It would be interesting to know what the 85th percentile speed was for the sign in the article.
A few decades ago I got a speeding ticket in Massachusetts from an officer parked under an unusually low speed limit sign. He said I had already driven past two signs with the lower limit, which I found to be true, so I decided to pay the ticket as punishment for my inattention – which I consider to be a worse driving habit than speeding.
A few years later when I went by that spot I found the limit had been raised. so my previous speed was now legal. Sometimes the engineers can beat the politicians.
ROY SCHWEIKER
Concord