Shouldn't Samurai CW base class gain not only Two-Weapon Fighting feat but also Ambidexterity feat? CW is a 3.5e supplement and at that time those two feats were combined into one. Thus, Samurai meant to be able to double-wield a Katana and a Wakizashi with minimum penalty without taking any feats, and even without Dex of 15+.
Frankly speaking, that is the only edge the class has. Can use two weapons in heavy armor and without high Dex. Without this class feature, CW version Samurai is a real crap.
Also, it seems that I can only take 20 levels of CW Samurai class. It is better I can take it 40 levels of it, because only few other classes has Intimidate as class skill (and some of them, such as barbarian, cannot be lawful).