gekrompen hoofd: The problem with your solution is that moderator reduction is as easy as getting rid of some moderators, it doesn't need a rule. On the other hand, if you insist on understaffing, especially with volunteers, you'll find yourself shorthanded when there really is a need for moderation.

I have moderated and administered a number of discussion boards in the past ten years. Those with lots of moderators were almost always better run than those with just a few.

Rules for the sake of rules don't solve problems. If moderators are such a large problem on this site, address why the problem causers can't be removed, don't simply remove random volunteers.