@seichel You are incorrectly equating Chabad practices and beliefs with “Chassidus”. Vizhnitz, Belz, Satmar, etc. don’t spend three hours a day to go over their late Rebbe’s happy birthday letters.
@nomesorah This is personal experience and things I’ve been told. In places where Rav Hirsch changed his mind, his earlier writings were not translated. The one well known instance is in “The 19 Letters” he says that he will write a sefer called “Moriah” in which he will define what Talmud Torah im Derech Eretz is. However, he never wrote the sefer and never wrote a clear cut definition of it because later in his life he felt that too specific a definition won’t work for later generations.
@DaMoshe Very well, then a Rebbe is someone appointed by his Chassidim. However, said Chassidim cannot appoint a book to be their Rebbe.