Either way, M. Snape's observations are in error, error, error. He is forcing his conclusion when none can even exist.
That is not logical. You have two elements 1) observations 2) conclusion
1) observation : observing how the cartouche was painted. No one here has presented HOW Jon's observations are in error. If they are wrong, HOW are they wrong? He has invited opinion on this, but no one is offering one. Example; the ring was painted starting at the bottom right moving upward and to the left and around. If you are saying this observation is incorrect, WHY do you say so?
2) conclusion: is interpretation of the observations. You may have a different conclusion. Observations may be totally correct, and conclusion incorrect.
Two separate steps.
You are not forced to accept his conclusion. You are completely free to dismiss conclusion. You are also free to present your own observations. Jon has asked for them but no one has critiqued his observations. Bitching is not sufficient to dismiss observation.