Someone who mistakenly believes that he is Napoleon presumably thinks that he himself is impressive intellectually, and in the artificial example I was discussing, he would think that others who believe the same thing are also impressive. However, it's also true that outside observers would not admit that, and in the cryonics case many people would, so in this respect the cryonics case is much more favorable than the Napoleon example. However, as Lumifer pointed out, this is not a terribly strong positive argument, given that you will be able to find equally intelligent people who have not signed up for cryonics.

In the Hanson etc airport situation, I would at least ask them why everyone else is in the long line, and if they had no idea then I would be pretty suspicious. In the cryonics case, in reality, I would expect that they would at least have some explanation, but whether it would be right or not is another matter. Ettinger at least thought that his proposal would become widely accepted rather quickly, and seems to have been pretty disappointed that it was not.

In any case, I wasn't necessarily saying that signing up for cryonics is a bad thing, just that it seems like a situation where you should understand why other people don't, before you do it yourself.