Never seen a gamie take a tape measure to an antler. Usually they will just stand back and think, either yup that looks like 2" or no way is that two inches. In short as many will say "if you are not sure don't shoot"! It really is not that difficult. I personally take a lot of pride in the number of deer and elk I have passed on because I was not sure of something. I think it has made me a better hunter.