An idea that's false but "spectacularly well-written" should be downvoted to the extent of its destructiveness.
Well, to the extent of its net destructiveness... that is, the difference between the destructiveness of the idea as it manifests in the specific comment, and the destructiveness of downvoting it.
But with that caveat, sure, I expect that's true.
That said, the net destructiveness of most of the false ideas I see here is pretty low, so this isn't a rule that is often relevant to my voting behavior. Other considerations generally swamp it.
That said, I have to admit I did not read this comment all the way through. Were it not a response to me, which I make a habit of not voting on, I would have downvoted it for its incoherent wall-of-text nature.
Summary: I propose we somewhat relax our stance on political speech on Less Wrong.
Related: The mind-killer, Mind-killer
A recent series of posts by a well-meaning troll (example) has caused me to re-examine our "no-politics" norm. I believe there has been some unintentional creep from the original intent of Politics is the Mind-Killer. In that article, Eliezer is arguing that discussions here (actually on Overcoming Bias) should not use examples from politics in discussions that are not about politics, since they distract from the lesson. Note the final paragraph:
So, the original intent was not to ban political speech altogether, but to encourage us to come up with less-charged examples where possible. If the subject you're really talking about is politics, and it relates directly to rationality, then you should be able to post about it without getting downvotes strictly because "politics is the mind-killer".
It could be that this drift is less of a community norm than I perceive, and there are just a few folks (myself included) that have taken the original message too far. If so, consider this a message just to those folks such as myself.
Of course, politics would still be off-topic in the comment threads of most posts. There should probably be a special open thread (or another forum) to which drive-by political activists can be directed, instead of simply saying "We don't talk about politics here".
David_Gerard makes a similar point here (though FWIW, I came up with this title independently).