One trick an experienced panel beater let me in on was when you are feeling for small dents with your hand use your other hand , not your dominant hand, if you are right handed you will feel a tiny dent much easier with your left hand
Yes I have seen that done.
I have seen some one who was beating the light rims for a 1940's Humber small work.
He used his nose.
He took off me a few old steel body CO2 extinguishers. After I emptied them as formers.