Straph wrote:
It does say in IUS that you can hold something in your hands and still use IUS.  It doesn't say that you can use, or be armed with those items in the hands.
This rule specifically works around that concept of it doesn't say you can't.  Even though technically you can't wield both weapons without a feat (multiweapon fighting), and multiple arms.
My misunderstanding of the 5 foot step also makes the above less broken.  As you can't continually trip them after taking multiple 5 foot steps each round with a full attack.  So it balances slightly better than I thought.  Thus I agree that you could do it.  As it isn't as broken as I thought it was.
You clearly don't understand the rules regarding AOO if you're still arguing this. IUS does several things for a character: namely, the ability to deal lethal damage with unarmed attacks and to be considered armed when not holding a weapon. The feat (or monk/brawler class ability) does not convey the ability to perform an unarmed strike while holding items in both hands. Anybody can do so, but the damage will be non-lethal without the feat or class ability. Your fighter can always opt to kick something rather than swinging his greatsword at it in combat, but it's such an inferior option that why would you ever do it? Okay so far?
Now, all the commentary about flurry of blows has no bearing on AOO whatsoever. FOB is a full-round action, and therefore has nothing to do with AOO, which is a free action in response to an enemy moving through a square that you threaten.
Similarly, TWF has no bearing, because it simply lessens the penalties of attacking with weapons in both hands. It does not convey the ability to do this, it simply makes it easier by lessening the penalties on attack rolls. Again, just as with unarmed strikes, anybody can do this without the feat. Multiweapon fighting goes even a step beyond this, because you need three or more arms to even take the feat. Similar to two-weapon fighting, it makes it easier for a character to attack with multiple weapons, but they can still do it without the feat! If you're holding a weapon that you can potentially swing, even if you're not proficient or it's an improvised weapon, you are still wielding it!
It's ridiculous to assert that if a monk is holding a weapon or weapons, they are not considered to be "armed" with them. That's exactly the opposite of how it works. It's actually part of what makes playing a monk versus creatures with different types of damage-typed DR so great. You can be wielding a pair of slashing or piercing monk weapons (which incidentally, the only thing that the monk special does on a weapon is let you use FOB with it, which as stated above when I was talking about FOB, has nothing at all to do with AOO) and still do bludgeoning damage instead by using kicks or elbow strikes (or even headbutts if that's what you want to use for flavor) with IUS.
Now, getting to the point of all of this: the reason that IUS lets you threaten adjacent squares is that you're considered armed with your unarmed strikes (while those without the feat/class feature are not). Therefore, you can threaten with unarmed strikes. A fighter holding a reach weapon only threatens the squares that are at the reach distance (say 10' for a medium-sized fighter), but not the adjacent (5' away) squares, because while he can still kick or otherwise attack with an unarmed strike, he's not considered armed while using them and therefore does not threaten with them. However, with IUS or the class feature equivalents, you do threaten with unarmed attacks, and therefore you would still threaten adjacent squares, regardless of whatever the monk is wielding any weapons or not. I don't think this is the point that's been disputed. However, if the monk is wielding a reach weapon, he still threatens those adjacent squares in addition to the squares he can attack with the reach weapon. He's obviously wielding the reach weapon, and therefore threatening with it, and he's always wielding unarmed strike by definition. He can't not be considered armed with his unarmed attacks, and he can always use them.
I don't get how this could ever be considered broken, because AOO is a single attack free action that you can only do a limited number of times per turn. You can't move during it, you can't do anything but make a single attack. This just makes it more difficult for an enemy to close in on a monk to attack it, because it can always use the withdraw action to take no AOOs. Please, please, please explain to me why an increased threatened area on a monk is broken? Large creatures with reach have the exact same threatened area!
I'm going to stop now before my head explodes...