If you check the edit summary for you question's [2nd revision][1], and nhinkle's [comment][2] on your answer, it seems that people are confusing that answer for an edit to your question. They think you're providing an *update*, not an answer.

And I can see why - you've just dropped a command with no explanation of why or what it does. This is something that happens quite often around the site by people incorrectly 'answering' their own question with something that should be an update. The action in these cases is either straight-up deletion or conversion to an edit.

This means that when you *do* genuinely want answer your own question you should make it clear that you consider what you are posting in the answer to sufficiently and correctly solve the problem.

[1]: http://superuser.com/revisions/368830/2
[2]: http://superuser.com/a/368831/39366