Here is what I believe happened in that referenced exchange: You wrote a comment that was difficult to comprehend, and I didn't see how it related to my question. I explained why I asked the question, hoping for clarification. That's a failure to communicate, not a failure to update.
My interpretation, having read this comment thread and then the original: Cyan brought up a subtle point about statistics, explained in a non-obvious way. (This comment seemed about as informative to me as the entire post.) You asked "don't statistical procedures X and Y solve this problem?", to which Cyan responded that they weren't relevant, and then you repeated that they do.
Here, the takeaway I would make is that Cyan is likely a theory guy, and you're likely an applications guy. (I got what I think Cyan's point was on my first read, but it was a slow read and my "not my area of expertise" alarms were sounding.) It is evidence for overconfidence when people don't know what they don't know (heck, that might even be a good definition for overconfidence).
Say what I would have written differently if I were not overconfident.
After Cyan's response that Gibbs and EM weren't relevant, I would have written something like "If Gibbs and EM aren't relevant to the ideas of this post, then I don't think I understand the ideas of this post. Can you try to summarize those as clearly as possible?"
[Summary: Trying to use new ideas is more productive than trying to evaluate them.]
I haven't posted to LessWrong in a long time. I have a fan-fiction blog where I post theories about writing and literature. Topics don't overlap at all between the two websites (so far), but I prioritize posting there much higher than posting here, because responses seem more productive there.
The key difference, I think, is that people who read posts on LessWrong ask whether they're "true" or "false", while the writers who read my posts on writing want to write. If I say something that doesn't ring true to one of them, he's likely to say, "I don't think that's quite right; try changing X to Y," or, "When I'm in that situation, I find Z more helpful", or, "That doesn't cover all the cases, but if we expand your idea in this way..."
Whereas on LessWrong a more typical response would be, "Aha, I've found a case for which your step 7 fails! GOTCHA!"
It's always clear from the context of a writing blog why a piece of information might be useful. It often isn't clear how a LessWrong post might be useful. You could blame the author for not providing you with that context. Or, you could be pro-active and provide that context yourself, by thinking as you read a post about how it fits into the bigger framework of questions about rationality, utility, philosophy, ethics, and the future, and thinking about what questions and goals you have that it might be relevant to.