I don't live in areas like that , 30mph is slow enough around these partsI often get to do 10mph or less on m1 and m25.
Through London it's often difficult to achieve 20mph.
That's as a motorist not a cyclist.
On my local roads 20mph is probably the best average .
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It's great to complain about lower speed limits, but in the real world they are often unachievable limits.
It must badly affect those that want to do 40 or more