So presumably this includes the possibility of writing 100% positive articles on CrunchFund funded companies and 100% negative articles on their competitors....
That said, I really don't see why Arrington would want to try wearing both hats. It brings a huge magnifying glass onto the bias in his articles, and possibly the articles of all those at TechCrunch.
A set of "rules" that sounds good to outsiders but lets insiders do what they want.
Most "code of ethics" make it easy for insiders to call outsiders "unethical" for doing things that insiders do.
For example, "journalists" are allowed to make up quotes. Outsiders aren't.