In my opinion, if HN doesn't want puzzled people to ask why they've been downmodded, then instead of putting a line in the Guidelines saying "don't do this", they should separate the downmod into "I disagree" and "flag this as a bad comment", with the latter item the one that reduces the text weight. It's clearly broken - people have been doing this for as long as I've been here, and it's not going to change (sadly, 'it' means both the behaviour, and HN's braindead downmod mechanism).