Jothar, the yeshivishe world has very similar ideas except they don’t call it meshichism, they call it daas torah. They also go to gedolim for brachos and tefilos. Each believes his leaders are infallible and have a special connection with the RBSH.
One only needs to read the literature of various tzedaka mailings which claim that special cures will come from donating to that particular tzedaka because such and such a gadol has donated in the past or will give a bracha to people who donate to that one tzedaka. They never say that it is the zchus of the mitzvah of tzedakah, because every tzedaka has that power. It is because it is the tzedaka of so and so that gives it magical powers. All chasidim believe that eating the Rebbe’s fish, or soup or schnaps has special segulos.
At any rate, I feel bad for Chabad because they miss their Rebbe terribly, and haven’t adjusted well. As far as “the Rebbe helps”, there is a klal of tzaddik gozer vHKBH mekayem. And the seichel is called chelek eloka mimaal. All groups belive in meilitz yosher, etc. True, some chabadniks take it to an extreme, but as far as I am concerned, fighting among groups is far worse than anything Chabad does. We all saw the beauty of the movement with the Holtzbergs HYD.
What I am saying is that if we all stopped fighting, I am willing to bet the RBSH would overlook just about all of our flaws.