meic wrote:I am taking about a vehicle travelling at a speed such that it becomes a hazard in that context equally as much as driving in excess of the prevailing limit. It was advice I was given as a learner driver, and is still the advice now, seemingly https://www.theorytestadvice.co.uk/driv ... ogress.htm
There is a difference between how you are expected to drive in order to prove competency and how you are expected to drive every day.
On a test you are obliged to make progress in order to prove that you are capable of doing so.
Once you have passed your test you are perfectly free to drive at a speed which is efficient for your vehicle. There is a significant fuel advantage doing 60mph compared to 70mph.
Look at this advice from the Department of Transport.
And indeed such a speed differential wouldn't attract any attention would it - at least not from me. I attach significance to the words "where appropriate" in that linky.
If however, as an example, a car was driving more slowly than 56mph limited vehicles on a motorway, then one might want to look at that scenario, perhaps?