I can't disagree with anything you say above. In a normal scientific environment, the NOTEs are the place that is used to capture the thoughts about why the researcher came to the conclusions he/she did. So when I have a qustion about the validity of a conclusion by myself or in a colaborative environment the work of another researcher, The NOTEs for a fact and/or the "source citation" is were we place our comments. This comment is outside of the genealogic environment, and certanly outside of FTM or GEDCOM. GEDCOM and FTM do have places where you can place a note, HOWEVER I do hear that you are asking for an additional evaluation/conclusion indicator that states, "This fact is proven." and you confidence of that statement. And I would be good with that!!
I agree that GEDCOM is a "Conclusion based" environment and not an evidence evaluation environment. It was never intended to be used for evaluation, it was ment to be used for data transmital "the facts and what led you to the conclusion." NOT "The data that wa available and the scientific methods used to come to those conclusion."
RANT ON: I have come to believe that FTM is primarily concerned with keeping FTM sufficiently "dumbed down" so as to keep getting new people into the hobby and eventually subscribing to their databases and are not concerned with such complications as this or incorporating historical names into a structure of place names. It will be interesting to see if the new ownership of ancestry will make a difference. I doubt it. The subscription database is the heart of its business model - FTM is one gateway to that cash cow. RANT OFF
Having worked for "a" software company that purchase 100's of companies, their actions over the years after the purchase proved that they were not interested in making the products better tools just better "money makers". The subscription/renewal base was most important. I can relate to what you conclude above.