First, a lot of those words would be bannable; if you'd like to refer to someone else in this thread as a "dick and an asshole," you're welcome to try and see what happens.
Context matters.
Second, I regret to inform most here that Devolution has the right of this (although Devolution is not always right, don't worry). The word "bitch" has specific connotations which make it especially prickly to work with. If I call a girl a "dick," I'm not suggesting she has man-like qualities which make her inferior to other women, I'm saying she's a mean person. However, if I call a man a "bitch," it is very frequently intended to imply that he is weak (e.g. if some guy complains about hard work, one might tell him to "stop being a little bitch.") or overly emotional, or effimininate in other ways, and to imply that this is bad.
This does not mean that "bitch" can never be used; again, context matters. If you are mad at the outcome of a sports game and post "son of a bitch! We almost won!" You will not be banned -- but it is an especially thorny word to use, relative to the other examples given like "jerk" or "asshole." So I'd be careful when using it. That's all.
This of course means that the rules are not hard, fast, clean, and simple to understand. We know this. We are trusting in your ability to be an adult and reasonably understand when a word is contextually inappropriate and when it isn't, and you're relying on us to know the difference. None of us are perfect; it's possible someone will be unustly banned on occassion (And we do rescind bans), while otherwise reasonable people sometimes say unreasonable things, but strict, simple codes of conduct are much worse, in my opinion. They assume you're incapable of understanding nuanced rules and provides an easy out for juvenile people who quickly figure out how to not technically break the rules, but still be an enormous jerk. If the rules are hard and fast, we can't moderate those people, unless they are breaking those rules in a clear, precise manner.