First of all, _all arguments for ultimate authority are circular by definition_.
Second, of course it works. God has authority in and of himself; when he speaks, his Words "inherit" that authority. It's like an official putting his seal on an official letter: once you recognize the seal to be authentic, YOU have not given IT authority, you have merely recognized the authority that it already has.
All this said...there's no need for us to recapitulate the disagreements between EO and the Reformed Faith here. It's all been done before. Here's a helpful article outlining some of the main criticisms that Protestant/Reformed would have of Orthodoxy: [A Calvinist Looks at Orthodoxy](https://www.opc.org/new_horizons/calvinist_on_orthodoxy.html).
But if/since you were in a Reformed church for 18 years (I would be curious, which one?), then I doubt any of these disagreements are news to you. Scripture exhorts us to grow in our understanding, grow in the grace and knowledge of Christ, the Holy Spirit is given to lead us into a fuller understanding of the truth, we are told to move from the milk to the meat, he has given us the many "helps" of pastors and teachers for two thousands of years in order for us to grow, learn, refine, etc. -- as the article (rightly, I think) states, the EO remains "undeveloped" and I would add, gently, immature. It avoids questions and doctrines that the Scriptures (namely, Paul) mark as essential (i.e., original sin, sovereign electing grace, Justification by Grace Alone through Faith Alone, etc.).
We would do well to hear the Word of God on these matters.
No. Church tradition is the ultimate, and the Bible is part of that tradition. "Therefore, brothers, stand firm and hold fast to the traditions that you were taught, either by an oral statement or by a letter of ours." 2 Thessalonians 2:15
