[Claud]

In fact, the normative form for the Creed when being used for catechesis or when prayed in Greek is without the filioque.

I haven't seen any Latin catechetical manual that does not have the filioque. But you're right on the Greek, and there's a good reason for it: The Greek ἐκπορεύεσθαι and the Latin procedere do not exactly mean the same thing.

Should this analysis pan out, both sides should be able to hold to their traditional positions pretty easily.

[Kolokotronis]

“I haven’t seen any Latin catechetical manual that does not have the filioque.”

I don’t doubt it. Now that I think about it, the idea of using the ancient version for catechesis came out of a joint commission made up of hierarchs and theologians years ago, maybe in the early 90s, as a recommendation. I remember that when it happened, one of our hierarchs announced excitedly that they had solved the filioque problem and that reunion was imminent!