I'm thinking on this metaphor and have an additional thought. Just like how fencing off a garden can result in greater growth of that garden, when you shut it off from the world around with too much "fencing" you start blocking off things that are good for the growth of gardens. Such as rain, sunlight, and pollinating insects. It's likely a delicate dance to find the perfect degree of fencing between open to the world to completely closed off, that results in the greatest flourishing of the fruit of the garden. In the case of FORUMS of ALL TYPES that fruit is flourishing of ideas. It's likely similar to the mechanics of a carburetor, it takes a bit of engineering to find the perfect mix of fuel and air. Having said that I personally don't find it frustrating that people who just sign up and then start doing arguably "suspicious thing" be temporarily labeled as having "suspicious behavior".