Ex Gingi's conjecture is what the Gr"a would or would not have done seeing 200 years down the line. Your argument is we can't know how the cherem affected the course of history, and I'm saying we have 200 years of history to prove exactly that. You still haven't come up with a single example of how the cherem tamed chassidus or prevented it from "going off the deep end."
In a diagram of how chassiddus deviates from what the mainstream was at the time with black as the mainstream (of course that may not really deserve to be a straight line) are the lines representing what actually happened (most likely green or blue) necessarily the same as what would have been? Would the changes have continued? How can I find a change that they made if the point is that the cherem may have PREVENTED further changes?
That chassidus has penetrated every sect of Judaisim is irrelevant to what I am writing since it is only the possibly tempered version.
Either way I recommend that you research the Gaon's reasoning from sources other than Chabad.
See the reasoning mentioned here
http://www.aish.com/jl/h/cc/48954961.htmlWhat worried the Vilna Gaon was not so much the Kabbalistic aspects of Hassidism (after all, he himself had studied Kabbalah) but the potential for producing another false messiah (like Shabbetai Tzvi whose story we covered in Part 51. The Vilna Gaon also objected to the Hassidic concept that God is "in all things" as too close to pantheism or the idea that everything was equally holy.(2)
[/color]He was also concerned about the concept of the rebbe (as the leader of each Hassidic sect was called) because he felt that the Hassidic concept that a person elevates himself spiritually simply by "attaching" himself to a holy person (a rebbe) was an idolatrous idea.
[/color]Another significant concern of the Vilna Gaon was de-intellectualization of Torah. The Hassidic movement was largely a movement of simple, uneducated Jews, and he worried that Jewish scholarship was going to be replaced by singing and dancing. A religion that was a synthesis of heart and mind would become all heart and no mind.
[/color]Finally, the Vilna Gaon, and many other rabbis strongly objected to the fact that the Hassidim had changed the text of the prayer as this was considered a serious break with tradition and wholly unacceptable.
There are those who will say that history has shown that chassidus would create false messiahs (leave that conversation to the thread already existing please)
If the concept of attaching to a rebbe is problematic then it still is as well as changing the text of the siddur and the shchita knives (not mentioned here) etc etc.
What other changes similar to or eventually more drastic than the siddur and shchita would have happened without the cherem?