Some EOs want that, others like the Joint Commission don't see it as needed. This rigidity can be found by some on the OO side in a parallel way.
Yes, fine. As you all see, we have people like Sirlankyknight in our church who somehow hold opinions that they recognize are at variance with us, and yet they keep showing up anyway. Individually, you can find all kinds of wacky opinions (not to imply that ArmyMatt's opinion is out of the ordinary, as I don't think it is, just that I recognize that there is a range). The point is that it's not like either of us can ignore that significant portions of our communions would immediately cry foul just because the joint commission has found or recommended this or that. The joint commission is not a Holy Synod. Its findings are not binding in any fashion.
In truth, if in "two natures" is a normal statement, then the Creed of Chalcedon is OK too. If OOs accept the Creed of Chalcedon and everything except for anathematizing Dioscorus and Severus as heretics, it would look bad for both sides that they could not agree when they accepted the same Councils, minus two anathemas, when churches don't even follow all their own anathemas, like anathematizing anyone who doesn't accept unwritten traditions.
But this is not reality, my friend. Again, the Armenians have never venerated HH St. Dioscorus. They object to Chalcedon because they recognized separately, at the Council of Dvin in 506, that this is not the faith of our fathers. And we agree with them. We don't care to 'save' individual personalities from condemnation if it is deserved (hence when Eutyches returned to his vomit, we cast him out too), but about the substance of the faith.
We're not playing a game of cards here. It's not about "I'll give up this, if you give up that, and then we can play together." One or the other side would have to change its approach to this matter in ways that I don't think either are willing or perhaps capable of doing.
I would recommend everyone who is actually orthodox to look for unity and trying to achieve it like Paul says, rather than looking for ways to keep Christians who have the same beliefs divided. If you can't list any specific, explicit belief that is different and you agree on everything when terms are defined correctly, then you have the same beliefs.
And I would have no problem with that as a general statement of how things should be approached, with the caveat that saying that this is how things should be doesn't actually make them be that way. As dumb as it is to put it this way, we aren't in communion until/unless
we're actually in communion. EOs can admire our people like Abba Matthew the Poor, or even chant some of our hymns composed by St. Severus (that they attribute to Justinian, according to their tradition), and still call us heretics. Heck, I see it online all the time. Bob Marley was "Orthodox" when convenient for them, and part of a heretical cabal of Ethiopian God-haters as necessary, too. And we have similarly mush-headed people in the OO Church too, I am sad to say, who are loathe to say before the Chalcedonians that we, and not them, are the true Church. Lord have mercy on us all. Agreement is one thing, and I think there are substantial areas where we
do agree (you and I in particular have been over this a lot recently, so I would hope that you agree), but they don't rise to level of sustaining open communion without precondition as already exists between, say, the Serbian Orthodox Church and the Georgian Orthodox Church on the EO side, or the Syriac Orthodox Church and the Ethiopian Orthodox Church on the OO side. Why? Because we really are not the same. We really are not.
That's not looking for division. That's recognizing the obvious. And if you believe in where you are, then there's no shame in it. It doesn't mean I hate you, or think you're all damned, or anything like that. It means that I don't believe that you have maintained the faith as we have. And for your part, your churchmen return the sentiment ten-fold. Glory be to God that at least we are dealing with serious people on some level, rather than the mess that usually passes for 'ecumenism', which is a race to the bottom at the expense of the truth. Lord have mercy.