Going back to your original example, "
20 0f 25 shots in a 3in radius", it's reasonable, especially when the number of shots in a group is quite large, to throw out a few shots if you "called" them as being bad shots.
Calling a shot bad means that
when the shot broke you said to yourself: "That shot was high and left." It doesn't mean you shoot a bunch of shots, go down to look at the group and say to yourself: "If I throw these two shots out my group size goes down by half."
