Hypersmurf said:
Notice that in the 3E version, the monk can only make an off-hand unarmed strike if he is using a weapon in his main hand. He can't make an unarmed strike as his primary attack, and then an unarmed strike as his off-hand attack, but he can make an attack with a kama as his primary attack, and an unarmed strike as his off-hand attack.
Which supports the premise we started with - 'unarmed strike' is a weapon, and you can't TWF with a single weapon... you need at least two.
Which is an entirely different matter - I'm simply pointing out that a literal reading isn't intended.
As to the possibility of not being able to TWF with one weapon - that simply makes things needlessly complex (as you could indeed use a weapon for it), and in any case, is mostly irrelevant in the old rules system: The old flurry was mechanically identical to TWF, although no "improved" or "greater" variants existed, so the effect of TWF could be achieved using a different means. In 3.0, in any case, this limitation was actually
mentioned, and in 3.5 it is not. The entire monk attack sequence was redesigned in 3.5 so although you are clearly correct that in 3.0 this was not possible, that's not so in 3.5. The 3.0 text merely illustrates the history of a phrase which you interpreted literally, and shows that this text was copied verbatim from a previous edition in which in was not intended literally.
The 3.0 texts are not mechanically relevant, so although they don't allow TWF with unarmed attacks that means little - after all, most of the text
was changed. The 3.5 edition as part of that change, no longer explicitly bans TWF.
A TWF-using monk is the logical extrapolation of two rules which weren't written with each other in mind. There are no balance issues I know of, no flavor issues, and no simple reason to ban it. If a DM wants, he can ban it, but I see no obvious reason to do so.