Earlier today, this answer to this question was converted to a comment by a moderator. The same moderator subsequently reconverted the comment back into an answer an hour or so later. One of the effects this had was that all comments (including my own) on the answer were also converted to comments on the question, which made it seem like I was commenting on the original question. I was not notified of my comment being moved in this manner. I don't really mind it having happened, but it did make me wonder:
What is the reasoning for the conversion in the first place (rather than, say, only deletion), and why was the decision reversed? Is there a general policy for when answers should be converted to comments, or indeed when the comments on those answers are themselves transferred to comments?
My main reason for asking is purely in the interest of transparency and understanding when such conversions might take place.