I remember reading years ago about a skill of some traditional tailors, possibly by special training or from experience. The skill was in judging by eye, to an unnatural accuracy, all the size parameters of a client without ever using a tape measure.
I have seen this particular skill used on film and TV to characterize old Jewish tailors. It's a bit of a trope actually. I should like to know the name for that skill, or its practitioner. I know some were trained in Gateshead UK so I think it has a British English term, although possibly the term is a Yiddish borrowing.