I do not think it means what you think it means.
Whenever you become anxious or stressed, outer purpose has taken over, and you have lost sight of your inner purpose. Your state of consciousness is primary. All else is secondary.
There are only two master keys, correct?
If you hold a master key I'm assuming it's a mult-use item (as opposed to single use items like potions) and you can unlock any lock you encounter in the dungeon for the rest of the game.
Is this correct? Does that door remain unlocked for other players? or do you require a key to pass through every time?
There are only two keys. Buy them both if you want exclusive access.
Each key is a multi-use key. Use it as often as you want.
If a person does not have a key they can not walk through the locked passage. Not even if they are following someone down the passage. I suppose that means the doors automatically lock after every use. (Note there is nothing in the game to mark "unlocked" doors. They don't stay unlocked.)
Teleporting is another issue. Locks don't stop teleporting.