What the Catholic Church teaches about itself is irrelevant. No one would accept that convoluted reasoning if applied to a political entity. And the Roman church is one. Other than Russians no one takes Russia's' self identity at face value. We define Russia by its leaders actions. The same is true of any other nation.
I read Hyslop's book. It's what historians do. I read endless Catholic nonsense as well. But I don't find either creditable. Your attempt at insult is noted. Your church is corrupt. It is marked as corrupt by its past and by its current history. Your clergy are exposed as immoral. You history as you present it cannot be sustained. Your doctrines are false. Open your eyes. Your self-identity depends on historically and scripturally untenable claims.
When you discuss doctrine here, you consistently twist logic and scripture. I think you know this. You must be aware of how much you have to dance to make scripture fit your hermeneutic. I think you're here for self verification. If you were here for a clear scriptural debate, you'd abandon everything but scripture. No reliance on church teachings, "church fathers" or tradition. Just the Bible. That you do not approach debate here in that way reveals a considerable amount of ambivalence over the validity of your church and your place in it.
And I reiterate, I'm not a Witness. I've never been one. I don't care how offended you are by Watchtower publications.