Article one notes the failure of the reunion councils of Lyon and Florence without describing what happened at the second of them, and the episode is worth telling because it shows the dispute nearly resolved by agreement rather than merely argued.
At the Council of Florence in 1439, after months of negotiation over exactly the questions article one describes, a majority of the Byzantine delegation, facing a collapsing empire in urgent need of Western military help against the Ottomans, signed the bull Laetentur Caeli accepting the Filioque, on the understanding that it could be read through the mediating "through the Son" formula article one attributes to Maximus the Confessor. Mark of Ephesus, the one Greek bishop present who refused to sign, returned home and led the rejection of the union; when the delegation reached Constantinople, clergy and populace overwhelmingly repudiated what their own bishops had agreed to abroad, and the union collapsed within years, never accepted in practice by the Orthodox world it was meant to reunite.
The episode set the pattern for every reunion attempt since: agreement is reachable among specialists and even among bishops under pressure, and evaporates on contact with a wider church that was not party to the negotiation. The most recent serious attempt to narrow the question by careful theological work rather than diplomatic urgency is the North American Orthodox-Catholic Theological Consultation's 2003 statement "The Filioque: A Church-Dividing Issue?", which concludes that the two traditions' formulas need not be understood as mutually exclusive, a conclusion considerably closer to Florence's substance than to its method, and one still awaiting anything like Florence's scale of formal reception on either side.