If you're about to submit a comment containing "I don't mean to be", stop and consider whether what you're submitting adds any value (as defined by the HN guidelines in this case) to the conversation.

This is telling: "There's a hell of a long conversation here, with a lot of qualifiers, but frankly I don't have the time for it." If you don't have time to contribute something meaningful why contribute at all?

The other problem with "I don't mean to be" is it's fundamentally dishonest. If you don't mean to then why are you doing it? If you must do this, just say "I'm about to be".