I understand that concept, except that the tone that was taken in his post and subsequent response to mine was just made to be snide. Instead of making an opinion and standing by it (which I would gladly upvote even if gray and it disagreed with my own personal opinion), he attacks the knowledge of a commenter via a generalization.
Making anonymous statements is essential in some situations, but in my personal opinion, I find it completely unnecessary in this particular one. If they had just gone with paragraph 1 and 3, then it'd be a perfectly fine comment. Instead it has a decidedly different feel and attitude which is then 'shielded' via a throwaway.
But by that point my account had been super-ultra-hellbanned. I couldn't even post. It wasn't until another user's complaint about being hellbanned made the front page that my primary account was promoted to merely being dead.
The point is: people use throwaway accounts because the HN community has demonstrated that it is simply not safe to use your primary account to say something controversial unless you have tens of thousands of karma.