You won't like my answer, but I'll give it anyway. 1st, as steve (Flieger) mentioned, the Mullen and I don't have to have the same opinion. But that's not my official answer. My answer is this:
Our society continues to change. It has become more and more politically correct. I believe this has actually become a detriment to our country. And Mullen's response (Position) is the politically correct response. There was a time when people were truly held accountable for their own actions. e.g. If a group of 10 kids were playing recess, and one of the kids started to pick on another kid and caused a fight, THAT KID would be forbidden to have recess as part of a punishment. NOW HOWEVER, the COMMON resolution is to take recess away from EVERYONE. Not just the person who was the problem.
And this is becoming common everywhere. 1 person is inconsiderate with smoking a cigarette around others, and the entire facility becomes non-smoking; instead of dealing with that individual smoker. 1 person is offended with the christmas holidays because their beliefs aren't being recognized, so they cancel all christmas events; instead of finding a way to accommodate the 1 offended person. 1 person comments inappropriately their personal opinions and feelings, and besides dealing with just him, (General McChrystal), you make a policy that basically says that no one should express their feelings and opinions ever.
So, my personal opinion is: Admiral Mullen is giving the "Politically Correct" answer, and his "Solution" is Wrong. Fortunately, it is "All Talk". It is not practical and almost unenforceable. People, including senior officers, are still going to discuss their personal opinions; especially in informal and private arenas. This will not stop, and logically it can not stop. But again, the admiral is simply spitting out the politically correct answer. He's wrong, but he's as much a politician as Biden, Obama, and Clinton. That's part of his job.