I would posit that just because the reason isn't obvious or understood does not mean it doesn't exist. As an analogy, reference the Kissimme(sp?) river in Florida. Engineers knew that it twisted and turned, but could see no reason behind it. So, in their ignorance, they tried to straighten it, only to find that they had inadvertently poisoned the everglades by removing the bends in the river. Again, it goes back to what I keep saying about arrogance and a lack of understanding.