...if you accidentally imported into the library, you cly select all the files in the event brower, and use relink to relink them to the originals outside of the library. Check back into the pack,age and all the files are replaced with aliases. Boom done...
Bret, thanks for mentioning this important point. It's easy to unintentionally import media with "copy to library", do some work, then realize you wanted "leave files in place" external media.
Using the consolidate method to move media out of the library works. However upon the original import within the library, FCP uses a different folder structure. If any on-disk files had duplicate names (even though in separate folders) FCP adds the suffix (fcp1), (fcp2), etc. to avoid a filename conflict. This is especially likely with Sony filenames like C0001.mp4.
The consolidate method of moving media out of the library works but (1) It required another physical move and (2) Some users rely on folder structure and filenames for recordkeeping.
I recollect that in past versions the procedure you mentioned would not work or might have been unreliable. However, I just tested it several times on Intel & Apple Silicon versions from 10.5.2 to 10.6.5 and it now works very well -- provided all filenames are unique. If the filenames are not unique, then relink will not work because the imported filenames were given (fcp1) suffixes and the original files have different names. This is another example of why all media filenames should be globally unique, not just in the current library but across all libraries and all archival storage.
There were significant relink changes in 10.4.9 for proxies, so maybe the above relink behavior changed for the original media files then. I can't remember.
You are correct, after the relink the internal files are no longer there.