A person should know where his cold bore shot hits and his fouled shot hits. Sometimes they are different. For me, I don't shoot a ML over 100 yards, so if my POI is 1-2" off I could care less with a ML. If I am going to a place where I plan to take 150-200 yard shots, then it matters. I would go to the range every day for a week takeing one shot in the morning. Then the next week, I would take one shot, clean/oil the barrel, and repeat that 3 or so days. That way I could compare cold bore fouled, and cold bore oiled.

Another thing a person should know IMO, is where your ML hits with a long term loaded shot. If I go for the whole 2 week season and not fired my shot off. I am always curious when I go to the range, to if the shot arrised what would have happened with my gun being loaded all week in all kinds of conditions. Usually I don't see more than a 1" POI difference. Its all about confidense.