Saying something is a "right" does not end the discussion. The Supreme Court has said very clearly, time and time again, that almost none of our rights are absolute. Even the First Amendment has numerous exceptions for unprotected speech types.
I agree pretty much point for point with Rob's original post. OC in an understated and respectful sense is a legitimate exercise of the 2nd Amendment. Open Carry activism, police baiting, and other such noise is the equivalent to screaming your political views in someone's face. Allowed? Sure, but after a while people will get tired of it, and whether it's a right or not they'll find the legal and political muscle to address it.