Perfect sense, midgey!
I remember the mattresses on my step grandmother's beds from a very expensive shop, had labels on each side, and top and bottom with months on them, to show (the staff, I presume!) exactly how and when they should be turned!
Perhaps manufacturers of mattresses that do benefit from turning may consider adopting that?
Anyway, Mr P (who is not speaking to me, another story) has just turned the mattress, I know not which way, so I will now make up the bed.
As I am generally speaking a nice person, I will refrain from putting prickly burrs or itching powder in his pillowcase.