I know some members have dropped off their posting/stopped posting altogether due to poor moderation and condescending replies to pertinent questions, it's a shame that people don't feel comfortable with posting for fear of derision/ridicule, which is why I feel that bantering ought to be allowed as it can draw in posts from newer members who perhaps don't feel experienced enough/knowledgable enough to post on topic. For the large part everyone seems to get on well and there are some good characters but not everyone is as anal about currying as some are lol. Most members want a recipe and nothing more, so there's no need to post really...a bit more of a light-hearted air around the boards may encourage greater participation by the wider masses...plus it makes the board look busier and more welcoming.
Cutting out the "dead members" (ones who haven't posted/logged in for a year) shouldn't harm anything and if there are members with zero posts, I'm sure they'd re-register to gain access to the recipes again though I know on some forums they have a minimum post count rule, i.e. anyone with less than five posts can't see the recipe sections which is never a good thing in my book as all you get then are one word posts lol