Yikes indeed, because when you import, if you are set-up to "Add", the files themselves aren't moving and no duplicate files are being created. All that happens is that the Lightroom catalog creates pointers to the files at their current location, scoops up the metadata and creates a preview (Standard or Full Resolution depending on your settings). So if you delete the file from your drive you're toast. LR is a file manager and editor, not a repository of the files themselves. Indeed, good to know! :-)