I have to disagree. Being able to obtain close enough accurate results without needing to calculate or measure is incredibly useful on a daily basis.
Ever had to pick the right size drill or screwdriver bit out of a mix? Thats the kind of skill this most often relates to.
combined with real measurement it becomes intuitive knowledge to verify my own measurements.
In school i just had to do extra work to be able to write down a formula. I agree thats not useful but i was still practicing the same algebra to do so.
Trying to remember the formulas from my head turned out to be literally impossible for me. I got a diagnosis post education and i may explain why i developed this ability from need to make up for my disability.