Pam, I just don't agree with you about this issue of hacking the law. Trademark law was designed to put political pressure on a racist instutition; it was designed to avoid consumer confusion about names and brands.
Therefore, the use here is hack like copyleft.
I get your point, your saying that the attack on the registration was an indirect way to force a social change. But here the "hack" is consistent with public opinion, not altering it. And it's a pretty lousy way to do it to; as I mentioned it's been going on for over 20 years and still has a few more to go. The Redskins will change the name first.
I've been engaged in discussion about whether these marks are enforceable at common law because they are not confusion-based. I thought clearly they must be, but others have convinced me I could be wrong. Mark McKenna takes a thoughtful view they are enforceable on a recent Patently-O post. Personally I think that a decision holding that they are not enforceable is a content-based restriction on speech, but I'm not a First Amendment expert. So to the extent that this means that the trademarks aren't even enforceable at common law I'd be getting closer to "hack," although I'd probably characterize it more as a excellent use of leverage.