Driving well below the speed limit

[jfollows]

M6 junction 15 (Stoke) is pretty horrible, especially in or following a low-powered car, I suspect it wouldn’t be allowed if it were being built new today.

 

[Ken H]

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I do support a 50mph limit on single track roads with no white line. It is clearly nonsense to have these at 60.
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While there are some windy single track roads, some are straight with good visibility. Some should be 30 while other should remain at 60.

There is a road near me that is well laid out with a centre white line. But in 2 places there is a narrow bridge and the centre line has a gap. Should just the short sections over the bridges be 50?