to think that politicians who are keen for a return to Imperial measurements should be asked to do calculations with them

[cakeorwine]

I know my weight in stones and pounds. And in Kg
My height in feet and inches. And metres / cm

I can visualise a mile - but a 1000 yards - not really.

But when it comes to calculations, I would struggle with Imperial but it's easy with metric

10 stones 5 pound 7 oz divided by 7

or 52 kg divided by 7 - I could estimate that pretty confidently and it wouldn't take too much time to calculate it.

3 lb 5 ounces at £1.23 a pound or 4.2 kg at £1.23 a kg?
And what is less than an ounce - you can easily go more precise with metric but with Imperial?

I know that 'in the old days' people got used to these calculations. But we've moved on.

If you want to display units in price per pounds or per gallon / fluid ounce, go ahead . But keep Metric.

I think politicians who are keen to do Imperial should be asked to do some percentages, division and multiplication with such units. And then they should be asked if it's worth it

Trading Standards are finding that it's unpopular to prosecute them. Local papers get involved, as do some Conservative MPs. If they are prosecuting a market trader for selling short weight they throw in the Imperial weights issue as well, but otherwise they won't nick them for the metrication issue on its own.