In summary, I don't believe you were understanding me correctly.

OK, cool. Thanks for answering my question.

To answer your questions...

Is MWI more like a sacred cow, more like Mormon magic underwear, or more like induction?

Beats me. I don't see how its especially like any of those things, though I can see how analogies to all of them might be sound, depending on how it's being used and by whom.

How many of the purposes of lesswrong do we thwart if MWI is not accepted as a given?

Twelve.

Is "cult of personality" a valid purpose of lesswrong?

It's not one I approve of, no.

Is "cult of personality" something to avoid for lesswrong?

I prefer to avoid it, yes.

Do the constant sniping of highly trained and educated, but "puerile" skeptics at our weakest beliefs serve us or thwart us?

I don't quite understand this question, and I'm not sure who "us" refers to, but in general competent expressions of skepticism are often valuable to a community, including this one, and sniping rarely is.

Does "catastrophizing" the claims of these skeptics in order to promote the dismissal of these skeptics serve or hinder the purpose of being less wrong?

Probably not, though it no doubt depends on specifics.

I think it is perfectly possible to make a bad choice about MWI (whichever direction that might mean) and still be a net plus by a wide margin to rationality. What do you think?

Sure, that sounds true.