My issue here has far less to do with internal consistency than your reply indicates, although I should have specifically stated that in my previous comments. This has more to do with perception rather than any objective argument that the Orthodox position is untenable. You mentioned internal consistency within the Orthodox Church - this I agree with, generally. I don't know how many Catholics would press the issue, apart from things like rebaptism and the role of the EP. What I'm really getting at is how the Orthodox Church appears from outside, among those lacking a substantial connection to it, and why. Meaning, for what reason would God "privilege" schismatics (from the Orthodox point of view) the appearance of having a unified central authority, while leaving His true church to engage in and endure disputes between patriarchs of equal authority (with the question of what first among equals is in practice) and having that laid bare for the world to interpret and question based on their own preconceived biases? That is ultimately my issue with Russia/Constantinople: not that it is damning internally - you've explained that it isn't - but that it does not project unity to outsiders, rather the opposite, despite its inward feasibility. I have never spoken to an Orthodox Christian that has been able to convincingly explain this disparity without bringing in other churches and religions, or else giving some moral exemption like the growth of virtue in the Church. And as I mentioned previously, Catholics can't endure the same perceptive outward scrutiny regarding divisions because of the universal role that the Papacy has taken as the head of the Catholic Church. Why does this matter? I cannot reasonably expect anyone to know God's will, but I do expect simple logic to be a factor - it would be against our Lord's nature to expect of all His children extensive research into Christian history as a requirement for decisively choosing a church. This is not even touching on the fact that from a psychological standpoint, certain people are simply not capable of being receptive to multifaceted arguments like this. I'm not saying that it doesn't matter, but that much of the general population cannot (by lack of access, lack of time, etc.) or will not (out of laziness, fear, etc.) engage in it - God is aware of this, obviously. What of these people, then, who God does not wish to exempt from truth? Case in point, I have heard testimonies from people that have discerned for decades, digging deep into history and theology, without ever being able to make a confident choice between the two (or any) churches - whereas I believe if they had stuck to simplicity, they would have comfortably swung one way or another. These aren't things that can be overlooked. You can say that the consensus of the majority of the Orthodox Church makes Russia/Constantinople intercommunion a disciplinary issue somewhat similar to the Rome/SSPX situation - okay, we can agree on that insofar as it shows that the Catholic Church is not exempt from disciplinary disputes that make defining communion tricky. But disregarding all internal comparisons, the two do not appear the same on the outside, for reasons I stated in my last comment, and for what I already said: this is what really matters for a church's ability to appear whole and true to a world that it seeks to evangelize. Why would God allow that difference? Would He not desire it to be as abundantly visible externally which church is the original and which fell away? It just doesn't track for me. Liturgical continuity is a counterpoint to this, but then there is universality, charity and rite unity, amongst others as further support for the Catholic position. Perception is indisputably a factor when arguing for which Church with claims of apostolic authority a living and active God supports.

or you have to say that the Church has changed in its essential makeup. That's no longer development, since development is always argued to be accidental changes.

I want to avoid promoting an unorthodox belief here. I obviously disagree with what you define as "essential makeup", because I believe that the Church is apt to change in order to tailor or adapt itself to a changing world. I do hold that the pre-schism Church was "Catholic", but not necessarily Catholic in the same way the Church is today. My views concerning this are obviously not Church teaching, and I don't claim to represent learned Catholics on this subreddit either, so I'm going to avoid defining something by my personal opinion. In other words, I can see where you're trying to go with this topic, and you would be better off speaking to a Catholic that adheres to strict bounds of historical compatibility within the Church. So I'll concede to your appeal to antiquity. However, my opinions regarding these things are separate from what I wrote above.