I recently had wheel nuts on my Volvo come loose, days after having had the wheels balanced. Luckily I correctly diagnosed the rumbling noise from the rear of the car on my regular Thursday 90mph run down the A2 and Thanet Way to lecture in Broadstairs, and tightened the nuts before my return, or I might well not have survived the return journey.

I saw the mechanic torque the nuts down with a torque wrench when the wheels were balanced. It transpires that it is standard advice that after you have had wheels removed and replaced, after 30 miles, check the wheel nuts.

I have been a petrolhead for many years and did not know that.

My point in this context is to wonder how often the nuts on a set of railway points (aka railroad turnouts in the USA I believe) need their torque settings checked in order to be safe.

A spinoff thought is to worry how often accountants and "private equity" investors think it cost effective and "efficient" to make such checks.