Why? What makes you certain of that? I'm not suggesting that Dan and Scott stop moderating, just that it's possible to make a clear, coherent statement about bigotry in the moderation guidelines.
My experience with moderating large communities and, mainly, my inability to define bigotry to any satisfactory degree. I certainly urge you to give it a go, maybe you'll be able to solve the problem for all of us.
Hell, I can't even ballpark where your freedom to speak ends and my freedom to not feel bad starts.