The response to dang's ban comment was posted in under a minute by my recollection (I saw dang's comment in the New Comment feed and by the time I browsed there the response was already in place).
'Ban' means ban but it can take a minute or two to take hold and thanks to a custom backend might still allow responses to ban notices - HN does allow people to talk themselves back from the brink once or twice if they engage and explain their actions and indicate they'll do better etc.
