Attached Link: Shaders Plus on Digital Carvers Guild site

Somebody once explained to me why it is impossible to do 'shadowcatching' this way, because there is no shadow to be catched in HDRI lighting. Just 'less light' to be shown. And you can't show something that is not there, can' you? Well. It sounded logical then. But. Enter Eric Winemiller: Shaders Plus has a GI Shadow Catcher feature. And much more that comes in handy by the way.