I think a group is typically the distance between the centres of the two shots which are furthest apart. A group wouldn't be a group unless there are at least 3 shots.If a 3 shot group of 2" is good, a 5 shot group of 2" is better. As for the flinch, you could toss it out, but that wouldn't be very honest now would it. The idea is, after all, to perfect all aspects of our shooting to arrive at tight, consistent performance. I believe the best answer is to keep all targets, date them, record distance, charge, bullet, weather etc., and any special notes such as "pulled the one on the far left- delayed ignition". I get your question though. If we don't have a standard in conversation how do we know? As for a goal, mine would be to extend my range predicated on the ability to land 6 hitsin 6 shots on a 6 inch diameter circle, for deer hunting. I'm glad you brought this up!