What I've noticed is that there is no singular event that all, most or even many protestants agree as definitive of when the 'Early Church' became the big bad Catholic Church (and thus, no longer worthy of our allegiance).

It's all very vague and general.  You can't get a protestant to pinpoint where the Church went wrong.  Traditional Catholics don't have that problem.  There might be a disagreement on whether it was 1954 or 1962 or 1965 but the event that changed the world in a dramatically awful way was the Conciliar Reform.  

Protestants tend to more or less repeat what has always been said by those who have defected from the True Church, but it is nothing more than a conceptualization.  They cannot give you a serious point in time or event that spurred (and justified) the protestant revolution.

I've heard Protestants talk about wanting to regain the "faith of the early church", as if there was something magically purer and more innocent about the faith of those who wrote Scripture and those who were under their teachings.

I've heard this too for the longest time from Protestants. When I raise the point that Mithrandylan made, they answer that the early Church after which they would model themselves is found in the Acts of the Apostles. However, I tell them that it was the successors of the Apostles who defined that Acts was to be enumerated in the Canon of Sacred Scripture centuries after the Apostles went to their heavenly glory. In fact, the Apostles and their disciples never had "Bibles" in the sense the Protestants do because the New Testament had not been completed.

It was the successors of St. Peter in the Roman Pontiff who faithfully guarded the deposit of faith and the Sacred Scriptures, because to St. Peter alone was infallibility promised for his successors. The Church came before the Bible, not the other way around.

The Protestants have mutilated the Sacred Canons and have derogated the doctrines of Christ and of the Apostles. If they had been in the "early Church" they would have come up with thousands of "Gospels" of their own making and would have preached contradictory things only to make Christ into a thing of mockery: as they have done for so long and still do so to this day.

For there to be "something", it has to be defined.

What are Protestants?

Each person is his own church of one, taking with him whatever he alone believes, that is what a Protestant is today.

There really are no group of people who agree on anything that can rightly call themselves Protestants. Each Protestant is his own church of one. Therefore, there is nothing that can be discussed about religion with them,  each person has to be handled individually.

This is true. "Protestant" has become too elastic a term, especially when used by secularists.

For example, what I posted above is something I could not discuss with liberals who deny the divine inspiration of Sacred Scriptures or the necessity of a set Canon of books in the Holy Bible.

As far as a time frame is concerned, our dear friend Jean Cauvin ("John Calvin") was noted as saying that he was positive that the first 400 or 500 years (I don't recall correctly which) of the early Church were theologically and liturgically and doctrinally flawless.

Think about how many of the Church Fathers lived and died within those first 400-500 years. Think about all of the clear and unambiguous and precise statements of doctrine that were made in that time frame.  Many of the most unambiguous and plain statements of doctrine of the Catholic faith were made in those years and were matters of unanimous agreement for another thousand years afterwards.

Interestingly, some good friends of mine have been reading a book about the differences between Hebrew thought about religion and its effects on life and the Greek model of thought about religion. The Hebrew model, as it was in the time of the Patriarchs, a definite, hierarchical, systematic approach to worship, is unknown in the world today outside the Church, where the worship of the Temple has been perfected and carried forward in the true Faith.

It is the Greek model of thought about religion, a system of rhetoric and argument that is designed to convince rather than command, is the modus operandi of all heretical sects claiming to be Christian.

That's why when someone formulates their own theological theories, they "join" a so-called "local church" because the rhetoric there agrees with what they already hold to be so. At whatever time the "teaching" (read = opinion) diverges from what an individual private person has determined, they either sit in the meeting and silently dissent or they leave and charge the group leaders with "false teaching". Most will then go join another group, but some go as far as to establish entirely new groups on the grounds that they want to get to "the truth of the Bible".

No one can be told to obey because submission and obedience are not Greek/intellectual characteristics; they're purely the product of top-down revelation as opposed to linear argumentation.

Hobble, I was a bit late in up-thumbing your links. Thanks much.

Interestingly, it's not just the liberals who are disavowing any allegiance to the Canon of Scripture. I've even encountered hyper-Calvinist fundamentalists who are calling into question the orthodox Canon precisely because it was formulated and promulgated by the Church and these people clearly perceive a major difference between the Church of those centuries and their so-called faith today.

Unbelievable the lengths to which men will go in order to resist and defy the Church of Jesus Christ.

Kyrie eleison.

Immaculate Heart of Mary, triumph soon!

Most Sacred Heart of Jesus, have mercy on us.

The protestant visceral dislike of Our Lady will always baffle me.  It's the number one reason I think that protestantism is from Hell.  

Everything about protestantism is problematic but the dislike, sometimes even hatred and sometimes even mockery of Our Lady is the biggest clue out there that there is something very "off" about protestantism.

Our Lady is truly the destroyer of heresies.

Protestants' strong hatred of Catholicism prompts them to attack Our Lady because we hold her so dear.  I don't really think their incoherent heretical mistreatment of our lady is based on much more than that.

How can the heretics of ages past and of our day understand the Athanasian Creed, for example, without understanding the indispensable role Our Lady played in the Incarnation of Our Lord. If you begin denying or outright despising Our Lady, sacred Symbols of the faith like the Athanasian Creed become ultimately irrelevant or meaningless.

Here is a treat that show how rich our Catholic heritage is.

From The Mirror of the Blessed Virgin Mary (Speculum Beatae Mariae Virginis) and The Psalter of Our Lady (Psalterium Beatae Mariae Virginis) (trans. Sr. Mary Emmanual, O.S.B.; St. Louis, MO: B. Herder Book Co., 1932), here is an English translation of the Marian adaptation of the Athanasian Creed made by the great Seraphic Doctor, St. Bonaventure: