I ran a test like this a couple of times and I still get blotch artifacts, so either I'm not setting it up properly or Larry's idea does not work.  A couple of pics showing the setup are coming shortly.  This particular render is at pretty high quality settings, and it doesn't seem to be any better at lower settings.  This is with sample radius at 20.  What really bugs me is that I'm getting almost no occlusion shadow, and where I do, it's a blotch.  The other shadows are actual rayraced shadows cast by the direct light (point light) in foreground left.

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