Maybe I'm a little slow on the uptake, but after watching it again last night, it became clear that the episode was another slam aimed at the network censors. While the "Family Guy" episode demonstrated that the censors won't allow depictions of Mohammed, but are okay with showing Jesus and George Bush crapping on the American flag, the "Metal" episode exposed (so to speak) the absurdity of allowing graphic depictions of breasts as long as they're anywhere but in their customary place on the female body. Pretty bizarre if you ask me.
Vic