IMO, weapon groups from UA make a bit more "sense".
also, why are intelligent undead immune to mind affecting?
Frank and K really did the best job of fixing the undead thing but....
I like that, rule actually.
Here's my explanation for this phenomenon.
The Mind & Soul are gone from that body. What your basically looking at is a negative energy based copy of that system (mind and soul). Which is why traditional mind and sould tricks don't really work on them.
Further this is why they are then able to be rebuked and turned. Thus doing things like "cowering" and being dominated. Its basically an interface problem at that point.
Example:
I have an X-box360 (Cleric with a high rebuke)
You have a Ps3 (Beguiler with dominate monster)
We both purchase a new game "Left 4 dead2"(the undead in question) lets say? If you mistakenly get a 360 version of that game you will never be able to play it on your system ... ever.
Why? It isn't that there's zero information on that disk. Its that your operating system is COMPLETELY DIFFERENT from the needed technology.
Which is why undead even intelligent ones are immune to mind-affecting effects.
They don't have brain patterns they don't have the same inputs, the have the same information sometimes (memories from life etc) but its running on a diffrent format. . .
The negative energy standard, format.
See? Now you can play in good conscience. CO makes everything better.
(just don't ask me where slaymates come from) edit: 5 posts were put up as I wrote that explanation out. God I love this stuff. M_V