Mormons - How could anyone buy into it?

I have no idea what your point is.

If a person believes in a benevolent being who created the universe and exists outside the laws of the universe, yet for which there is no objective evidence, is it unreasonable to consider such a person a fool? YES - I believe it is unreasonable to consider such a person a fool. I disagree with the belief, but I don’t consider religious people to be fools. I believe that the majority of religious people can differentiate between the standard of proof for, say “Christ died for my sins”, and “John Doe is guilty of murder beyond a reasonable doubt”. Don’t you?

Does it constitute insanity? No, I don’t believe it does. The vast majority of the planet believes in a god. To call them all insane begs the question of what sanity is. In my opinion, they are all wrong, but not insane.

I disagree. There is no such thing as “personal evidence”. There is either evidence, or there is not. If the “evidence” exists solely in the mind of the believer, then it is called faith. Calling it by another name doesn’t change what it is.