For an experienced shooter, it appears to have correct analysis.
For a new shooter, however, it seems like it would be distracting more than it would be helpful. One of the common mistakes made by new shooters is to correct every shot. It's one of the reasons some shooters never (ever) become proficient.
New shooters need to focus on the mechanics of proper technique first and foremost. Using a small caliber to start can greatly assist in developing good habits.
Aha! Calling it an error is the error. Notice I didn't call it an error....
What happens is when a new shooter points the firearm at the bullseye and misses, they start to try to correct their aim by pointing somewhere other than the bullseye. For example, the shot hits low and right and the new shooter aims high and left on the next shot.
That's the mistake.
Proper shooting involves aiming for the bullseye on EVERY shot. After five shots, all the bullet holes should be relatively close to each other in a small group. Regardless of where this group sits on the paper, it should be a relatively small group and the smaller the better.
What that does is give you a good idea of where the rifle aims. After about three or four consistent groups on as many different targets, the sights may be adjusted but even then, we don't always adjust the sights. It's much more important to get consistent, small groups.
If we can't get a consistent tight group anywhere on the paper, we can start to assess the shooter more closely after a couple of four- or five-shot groups. Where the shots fall on the target may help to determine the failings of the shooter but for a new shooter, it may not help much.
Anyhoo, focus on getting group sizes as small as possible when you get your first rifle. If the groups are WAY off center, still focus on getting the groups as small as possible by aiming for the bullseye on EVERY shot. If you can do that, you'll be a long way ahead.
But the key here now is, what's the right shooting technique. Your next homework assignment! LOL