Dear Fr. Gregory,
Many thanks for your helpful and informative discussion of this topic; the last paragraph beautifully expressed a profound truth.
As we know, heretics such as Arius and Nestorius were both ordained in line of Apostolic Succession in the Church, and that was no guard against their mistaken views.
Apostolicity was one of the ways in which the early Fathers recognised what was and was not Holy Scripture; but as we can see from their writings, other ways were also found necessary. The test of orthodoxy; was what was in the writings against what the Church had received from the beginning? There was also a test of catholicity - had it been received everywhere, by everyone from the beginning?
None of these things prevented debates of some fierceness, nor yet ruptures in communion between those who would describe their Church as having Apostolic Succession; but such failings are to be expected of us, and perhaps emphasise our need for Him.
The Ignatian model which the BOC follows has done excellent service for as long as we have any record of how the visible Church.
In this is love, not that we loved God, but that He loved us and sent His Son to be the propitiation for our sins. (1 John 4:10)