I think its pretty easy to tell. When the Pope says something along the lines of "I solemnly declare, define, etc..." or "All Catholic must believe..." He is speaking ex cathedra.
Precisely why Unam Sanctam and Cantate Domino are infallible although modern Catholics react with horror to the doctrine in them.
The argument you are providing sounds alot like when we Catholics accuse EOs about not being clear on dogma.
Unam Sanctam and Cantate Domino fulfil the criteria for infallible papal teaching but Catholics wish to fudge it.
When the Church says that they do not fully express the mind of the Church then they do not and are not infallible documents. Again I ask you: Who are you?
You goal with this kind of post is not to shed light but to shed heat and discord.
Your rages, the ones you claim to have, seem to me to hide the fact that you are terrified that there will be union in your lifetime and rather than ever be angry with you, I simply pray that you get to see it before you close your eyes on this side of the Great Divide.
It gives me great joy, morning and evening to pray for you so that you may live long enough to see the resumption of communion between Catholics and Orthodox.