I've had a LUKS system corrupt on me once (no biggie, I had everything backed up), it just happened when my battery died and when I turned it back on, my password wouldn't work.
I don't know whether that's a reliable way to always corrupt a LUKS key but I'm curious.
Do you guys know? I like the idea of someone demanding your password and you being able to honestly say "... I don't know what it is anymore... I can give you my old password?"
Mainly I want to know to figure out what causes the corruption for curiosity's sake.