The question that started this thread implies that a Chassidus is viable if it has a Rebbe. This, in itself, must be questioned, because it depends on the Rebbe In the case of Chabad, the Rebbe convinced his followers to become obsessed with his belief that he was(is) Moshiach, and this informs their very existence. On the other hand, if you had a Rebbe, like the Sfas Emes(my favorite) who made Torah study the sine qua non of life, I think the movement could go on quite well without a Rebbe.
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