I'm a big fan of the saying "Learn from other people's mistakes, because you'll never live long enough to make them all yourself."
Even in survival, practical "hands-on" experience can lead you astray. As Laurence Gonzales said, often "experienced" simply means "someone who's gotten away with doing the wrong thing more often than you have. " (Quoted from memory)
It is probably true, though, that a lot of what gets written in "survival" manuals is put together by people who read it somewhere else and never actually verified it experimentally.
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"The mind is not a vessel to be filled but a fire to be kindled."
-Plutarch