En munk av tomma händer tar inte -4-straffproblemet för improviserade vapen.
James Jacobs, kreativ direktör Paizo, klargör detta på Pathfinder RPG forum :
The monk of the empty hand treats improvised weapons as if she were proficient in them, and can wield normal weapons as improvised weapons. This effectively has the same end effect as the Catch Off-Guard feat, but isn't a feat and thus doesn't use up a feat slot since it's a variant class ability. Thus, they do not take a nonproficient penalty when using improvised weapons. The text is not as clear as it could have been, I guess, but hopefully common sense can step in to bolster that if someone doesn't read this post?
(We COULD have simply said, "The monk of the empty hand gains "Catch Off-Guard" as a bonus feat, I guess, but that would have lost the flavor bit about how they often wield normal weapons as improvised weapons.)
Således behöver du inte ta Catch Off-Guard alls, inte ens för Improvised Weapon Mastery eftersom du inte behöver uppfylla kraven för Monk bonus-prestationer.