Found this example, related to the discussion, on Wizards site.
http://www.wizards.com/dnd/article.asp?x=dnd/fc/fc20011208a
What this shows:
* The offhand natural attacks take the Multiattack penalty but no others, even while fighting with 2 weapons (or a double weapon in this case).
* Taking those off hand natural attacks does _not_ penalize the primary hand iterative attacks at all!!
* Mind Flayers are cool.
Here's that hypothetical creature again. +4 creature BAB, 6 fighter lvls, natural attacks are 4 Claws, 1 Bite. Again lets ignore Strength for the time, as it has no bearing. Some one handed weapon in one hand, full attacking. Has none of the appropriate feats (multiattack, 2tw, Ambi)
Is this correct:
Primary attack with sword (iterative)
+10 base
-4 two weapon fighting penalty
-----
+6/+1 primary
Off hand attacks: 3 claws & a bite
+10 base
-5 Natural attack penalty
-----
+5 secondary attacks
This leaves us with a attack sequence of
+6/+1 sword, 3 claws +5, 1 bite +5 for a total of 6 attacks.
Adding two weapon fighting, ambidexterity and a light weapon in one of the other claws, our new attack sequence is:
+8/+3 sword,+8 offhand sword, 2 claws +5, 1 bite +5 for a total of 7 attacks.
If anyone has a variation on this that I haven't covered, or seriously disagrees with my interpratatoin of the Fight Club monster, please speak up. As it is I'm basing this on just that one monster and I'm hoping he represents the rule rather than the exception.