There was a number of comments in this question, at least nine or ten, two of which mine, that were deleted completely not long ago. When I entered the question again, there were no comments at all. I clearly remember the points discussed in the comments and my replies. Those replies are gone from my own activity tab as well.
I think none of the comments were particularly offensive, and the wholesale deletion struck me as odd. I'm 100% certain I didn't delete my own comments. What happened here?