Are you encouraging people to break the law?

Under the heading 'Purring along' you seem to advocate driving at a steady 75mph on a motorway. I am under the impression from the Highway Code that the maximum speed on motorways and dual carriageways is 70mph. So, unless I am mistaken, it would seem that you are encouraging drivers to break the law. I am well aware that 'the law is an ass' (or words to that effect) and most drivers travel at at least 80mph if they have a vehicle capable of that speed with virtual impunity, but until the law is changed by the lawmakers I don't think that journalists should be encouraging people to break it. Do you agree?

Asked on 17 August 2013 by RC, via email

Answered by Honest John
Speedos are not allowed to under-read, but are allowed to over-read by up to 10 per cent. In fact, almost all over-read by at least 5 per cent. So 75mph on the average speedometer is between a true 67.5mph and 71.25mph. No one is ever going to get done for 71.25mph so, as you rightly condemn yourself, you are "mistaken". If you have a decent GPS system you can check this for yourself. Many TomTom GPS systems have the facility to show your speed 100 per cent accurately across the surface of the planet, including factory-fitted TomToms. They aren’t as responsive as a speedometer, but they are accurate.
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