Addressing 1) "Learning when you're wrong" (in a more general sense):
Absolutely a good thing to do, but the problem is that you're still losing time making the mistakes. We're rationalists; we can do better.
I can't remember what book I read it in, but I read about a practice used in projects called a "pre-mortem." In contrast to a post-mortem, in which the cause of death is found after the death, a pre-mortem assumes that the project/effort/whatever has already failed, and forces the people involved to think about why.
Taking it as a given that the project has failed forces people to be realistic about the possible causes of failures. I think.
In any case, this struck me as a really good idea.
Overwatch example: If you know the enemy team is running a Mcree, stay away from him to begin with. That flashbang is dangerous.
Real life example: Assume that you haven't met your goal of writing x pages or amassing y wealth or reaching z people with your message. Why didn't you?
I read about pre-mortem-like questions in a book called Decisive: How to Make Better Choices in Life and Work by Chip Heath and Dan Heath.
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