The unfortunate part is that I don't know what the course id from the git url until after I import it.  So I can't determine that until much farther down into the import tree.  What happens if I do overwrite an XML with a mongo store, won't the mongo store win?  Or do I need to re-architect this whole thing to somehow find out the course id before I import it by reading it out of the XML on disk?  If there is an unknown conflict issue there, it seems like that would need to be handled lower than my import since at least on the mongo path I'm just calling the modulestore's import command at the end of the day, wouldn't it know at that point?