IIRC, Vader used Lando's Carbonite-freezing plant on Bespin to test if it would be safe to use on Luke -- don't know if it's said so in the movie itself or in the novelization, but the Wook seems to agree with me on that point. So apparently (and his dialogue with Lando after freezing Han seems to confirm this) he wasn't sure if a human could actually survive being frozen in Carbonite... ...only later sources tell us that this self-same technology has been around an in use for millennia, as an (apparently common) method of burial, enabling pre-hyperspace long-range space travel, etc etc... and that Anakin Skywalker actually used it on himself during the Clone Wars. So... what gives? Has this point ever been addressed somewhere in canon? Or am I just too dumb to see the obvious fix?