When I worked for some years in a ramen shop I gained a visible callous on my thumb from peeling ajitama. I remember we would often have races to see who could peel a batch of something like 300 eggs first. I don't remember exactly, but it seems quite reasonable to me that an average time for those races would be under 10 minutes. Great to make Chef happy and have a little fun too!

The callous went away, but have a few more permanent burn scars still from those long long days and nights making tonkotsu with simply 100qt pots and large ranges.