All the MOA shooters here should fire a 10 shot group. Shoot it in a minute or two. The faster you can get back on target and squeeze off an accurate shot the better. Shoot ten, ten shots groups like that over a day, or a few days. Now average them. If the don't average one MOA or less, you don't have a MOA rifle.
Shooting one three, or five shot group that measures a MOA or less, proves very little. Other than the rifle is acceptable for hunting.
I've never, and I mean never, heard of anyone defining MOA under your terms. I've seen/heard arguements for 2 shot, 3 shot and 5 shot groups and debates over how many of those groups it takes to define MOA but 10 - 10 shot strings is so far above any accepted proof of MOA it's not even funny. You want the best test for a gun/load/marksman? One shot, cold bore. Nothing else should really matter. 10-10 shots strings = irrelevent.