There are some long lists of false beliefs that programmers hold. isn't because programmers are especially likely to be more wrong than anyone else, it's just that programming offers a better opportunity than most people get to find out how incomplete their model of the world is.
I'm posting about this here, not just because this information has a decent chance of being both entertaining and useful, but because LWers try to figure things out from relatively simple principles-- who knows what simplifying assumptions might be tripping us up?
The classic (and I think the first) was about names. There have been a few more lists created since then.
Time. And time zones. Crowd-sourced time errors.
Addresses. Possibly more about addresses. I haven't compared the lists.
Gender. This is so short I assume it's seriously incomplete.
Networks. Weirdly, there is no list of falsehoods programmers believe about html (or at least a fast search didn't turn anything up). Don't trust the words in the url.
Distributed computing Build systems.
Poem about character conversion.
I got started on the subject because of this about testing your code, which was posted by Andrew Ducker.
We can turn this into a mathematical-skill pissing contest if you like; for what it's worth, I don't much favour your chances. If you're talking about means versus variances: this is only a large effect when you're hiring from the tails of the distribution, and a lab-manager post doesn't require really exceptional ability in any domain.
The point of my specifying the job is that it's a job on which performance is (1) likely to be a matter of general competence in some broad sense, rather than specialized skill that, e.g., men might be much more likely to spend a long time learning for some cultural reason, and (2) sufficiently related to general intelligence that if someone holds that men are systematically better at it, it's reasonable to guess that this indicates they think men are smarter.
Knowing you're posting rubbish is not the same thing as posting something you know isn't well thought out. The comment I guess you have in mind here is not "rubbish", and its author's acknowledgement neither says nor means "I know I was posting rubbish". (If we truly adopted a standard saying that every comment on LW needs to be carefully thought through and made watertight before posting, then "who should 'scape whipping?".)
Especially on politics I would expect that people post what they consider to be carefully thought out or otherwise explicitly say that they haven't thought it through in the same post.
I accept that sometimes people think they have put careful thought into an issue but still end up wrong, but not even having the standard of careful thought before posting is bad.