Isn't there a slight problem whereby someone denies knowing the password, you just put them in front of the keyboard and just ask them to type something? Due to it being a subconcious memory, it 'just happens'.
It wouldn't necessarily 'just happen'. From what I can glean, the idea is that if you are trying to play the game as well as possible, then the portion that you originally learned would be played better. You could certainly intentionally play the entire game poorly, thereby masking which portion is the password.