Ok, but you seem to believe that this heresy was so absolutely total that it completely obliterated any trace of "orthodoxy" (as you define it) for 1500 years.
That is patently ridiculous. Even the most noxious heresies left plenty of traces--like people refuting them.
Claud, before the close of the New Testament *during the life of John, the Apostle* Christ showed him by revelation, that there was *already heresy in the churches.*
Orthodoxy was still mixed in, as it is today. But they took a turn toward falsehood. Some were correctable, according to Revelation and were warned to turn back. Others were condemned, and their candlestick removed. You can read all about it yourself. Christ said it.
So, no, all "traces of orthodoxy" were not removed.
Rome still mixes much orthodoxy with syncretic pagan practices and heresy, but had lost the gospel of grace hundreds of years ago.. in fact, slaughtered those who understood it.
Has Christ already removed her candlestick?