Yes ... that's exactly where it comes from and it is ancient. That said, in Iron Mike's defense, it is unlikely he has read much military history and is probably not a plagarist!
Quote from kut2k2:
This comes from the age-old military wisdom:
No battle plan survives contact with the enemy.
The market can't exactly be regarded as 'the enemy' but it will do unexpected things and only adaptable traders will stay on top of it.