What about requiring all new users to solve some different numbers of Euler problems to comment, vote, post top level, have cool neon color names, etc.? Alternatively or conjunctively, breaking up the site into "fuzzy self help" and "1337 Bayes mathhacker" sections might help.
Even assuming that this only filters out people whose contributions are unhelpful and provides useful exercise to those who are, it still sounds like too much inconvenience.
It can certainly be helpful to apply actual math to a question rather than relying on vague intuitions, but if you don't ensure that the math corresponds to the reality, then calculations only provide an illusion of helpfulness, and illusory helpfulness is worse than transparent unhelpfulness.
I'd much prefer a system incentivizing actual empiricism ("I will go out and test this with reliable methodology") rather than math with uncertain applicability to the real world.
Today's post, My Wild and Reckless Youth was originally published on 30 August 2007. A summary (taken from the LW wiki):
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This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was Say Not "Complexity", and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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