Years ago a friend, who was a U.S.M.C. 2112 precision weapons armorer, told me that they looked at the "muzzle art" to determine if the crown was properly cut. Good symmetry means a good crown. I don't really know but it makes for a good story.
I never noticed muzzle art till I got my 10/22 TD. This is my first stainless barrel so it might be it just doesn't show enough on blued barrels. I'll try to take a picture before I clean the next time. This thread should be extended it could be interesting to see the different patterns.