The whole idea of LOC is so that if there is a nuclear war or if a studio goes crazy and decides to junk all their prints or if people just simply forget about the films and they decay and get lost, this will be a safety back up that is protected by law from ever having harm come to it and safely stored in a very well-guarded federal reserve.

Of course, this assumes that the actual original is out there to be seen. No one can see the LOC prints, the whole point is to lock them away as last-ditch reserves. But in the case of SW and ESB they are "backups" to an "original" that no longer exists, in effect making them "originals" that we are incapable of viewing. Bizarre situation. Sending an email to them now, will report back if they confirm anything.