The Creed cannot be altered by anyone in particular, regardless what other theological interpretations exist. Which part of this do you not understand?
The purpose is for me to understand the Trinity. The opinions of fathers and doctors of the Church is very important, regardless of their dogmatic status. We just clarified that the Summa does not have such status either. I am, repeat, interested in opinions, not in conciliar process of altering the Creed.
I refer to the "Orthodox" whenever it is necessary to distinguish between them and the Catholic, and vice versa for "the Catholic". I understand that each side might have a larger claim, but my purpose is clarity of expression (even if on occasion I use one word while meaning the other). I apologize in advance, and I will stick to the labels that seem most clear for the context.
This is an important point. Individual fathers do not represent the Church, but rather the "consensus patrum" does. The Ecumenical Councils are a formal expression of this consensus of the Fathers, and there are other, informal expressions of the consensus of the Fathers that are also authoritative.
Individual Fathers can (and do) err or are unclear on this or that point -- that is why the Orthodox Church has never lifted one Father's teachings above those of the rest.
And the consensus view of the Fathers of the Orthodox Church has not only been that the filioque was improperly added in the West, but also that it is incorrect theology, with attendant implications and practical consequences for the spiritual life.
There are of course many modern Orthodox theologians who wish very much to finesse and avoid this issue, but that is because they wish to be nice, and because there are adverse consequences in the modern age to state that one doctrine is correct and that another one is incorrect. It just isn't nice.