Why does being surprised imply being miscalibrated? I should be surprised that a 100-sided dice rolled a 100 even if it genuinely is fair. If I weren't surprised by that event, I would say that I was miscalibrated. Of course this means that I should expect to be surprised every now and then, but what's wrong with that?
Why should 100 be any more surprising than any other number?
Information that surprises you is interesting as it exposes where you have been miscalibrated, and allows you to correct for that.
I suspect the users of LessWrong have fairly similar beliefs, so it is probable that information that has surprised you would surprise others here, so it would be useful for them if you shared them.
Example: In a discussion with a friend recently I realised I had massively miscalibrated on the percentage of the UK population who shared my beliefs on certain subjects, in general the population was far more conservative than I had expected.
In retrospect I was assuming my own personal experience was more representative than it was, even when attempting to correct for that.