This may interest you:
I would hope you agree that HOW we determine the "actual lived practice and faithful witness of the churches who received the Apostolic preaching, teaching and example" is by how closely their beliefs comport with the written word of God. Paul said "stand firm and hold to the traditions that you were taught by us, either by our spoken word or by our letter." (II Thess. 2:15). He also admonished, "See to it that no one takes you captive through philosophy and empty deception, which are based on human tradition and the spiritual forces of the world rather than on Christ." (Col. 2:8)
I believe, as Paul also stated, that "we also have the prophetic message as something completely reliable, and you will do well to pay attention to it, as to a light shining in a dark place, until the day dawns and the morning star rises in your hearts. Above all, you must understand that no prophecy of Scripture came about by the prophets own interpretation of things. For prophecy never had its origin in the human will, but prophets, though human, spoke from God as they were carried along by the Holy Spirit." (II Peter 1:19-21)
We are all familiar with Jesus' reprimands of the religious leaders of that time who substituted the traditions of men for the commands of God. If this method of determination was good enough for the Lord Jesus Christ and reiterated by the Apostles it should be for us as well. The authority of God's written word will always trump the traditions of men, no matter how faithful they have been.