I am not convinced of that. The opinion I hear from Catholic apologists such as Karl Keating is that every time the dogma is examined by both parties, no disagreement is found. For example, there is no dogmatic disagreement with Filioque, -- both sides agree on the dogma of Trinity and the provenance of its persons, -- there is an argument over the rite, essentially. But we have many rites, and some, legitimately, don't say "filioque". The Catholics are left with the impression that the Orthodox want there to be a disagreement and when one is resolved find another.
My remark beggining "I am not convinced of that" referred to your "The differences that the Church has with Russia are founded on dogma", and not to your entire #10, which I enjoyed reading, but find myself incapable of further comment.
One Orthodox man explained to me his version of the story when his ancestors went to Mass in the Roman rite and heard the choir chanting the Creed in Latin. They thought they knew it until they realized they were hearing one new word, he explained. They checked it out, and discovered that Rome had officially inserted the word, Filioque, into the Nicene Creed. When they took issue with this, the Roman authorities would not retreat from this practice and held to the new version tenaciously. This difference was never resolved, he said, and that's why we still have this irreconcilability today.
In light of the practical doctrinal questions of today, e.g., contraception, abortion, women's "ordination," homosexual "marriage," euthanasia, etc., the longstanding doctrinal question of the processions of the Blessed Trinity might seem like a moot point.
However, for anyone who has studied a good course in philosophy, it should not seem so moot. In fact, such things as these examples of "practical questions" can easily be understood to be caused by objectively larger principles such as some aspect of the Blessed Trinity.
It seems to me that the Roman authorities (presuming this man's story is accurate) had based their decision to add the word, Filioque, to the phrase, "...qui ex Patre procedit," because of a sound theological principle, namely, the procession of the Holy Ghost from the Son (to the Father, and, by extension, to their creation as well). When it comes to such principles, getting it right in the beginning inherently avoids all manner of erroneous consequences down the line, not that the identity of the consequences need to be known in advance, because error, once taken in and believed, begets more error. In the end, the Faith is ultimately destroyed. That is why it is true that to become a heretic, one only needs to reject one single point of dogma. And that is why someone who refuses to believe in something like the Filioque teaching is, by their own act of denial of truth, a heretic.
How many centuries do we need to live through before that principle becomes evident? The Church Fathers who recognized it in the beginning did not need to have any centuries to think it over, did they?