A.S.K. your way to proof.

[Jehanne]

Have you read the Council of Constance:

Council of Constance

in particular, #2, which states:


Do you regard Arianism as being a form of "orthodox" Christianity?

All heretics refuse to accept the authority as constituted by wider communities. 
I could care less about all the various little heresies THAT DIED OUT. 
Were these heresies incorporated into church doctrine ? No. 
You seem to be unable to see the forest for the trees. 
The fact is, the Nicaean Creed is still the same and still recited by most Christians.

You've actually made my point for me.
Of course there were heresies. That in no way means the church in general accepted them.
The fact that there were all kinds of heresies that arose, but were rejected, as not comporting with what the church's
doctrines, demonstrates that there WAS a body of belief they felt was not in agreement with the core beliefs.
Heresies are no threat to orthodoxy if they are rejected.
If you have examples of heresies that were ACCEPTED by the main bodies of the churches, let's see them.

Arianism was an orthodox view that simply could not compete with Triantarism. Once again. was Arianism a heresy? (Answer: No, Aranism became a heresy, largely, because of the Emperor Constantine's instistance of religious unity within his empire so as to foster political unity.) But, even after the Nicene Creed became "official", why did Arianism persist within Christendom? You might want to read the Nicene Creed, and, in particular, the Creed's statement of Jesus' Parousia and Christendom's reinterpretation of that so-called "dogma".