Exactly. Valuable if you want to ensure the confidentiality of the data no matter what - but you'd better really mean that "no matter what", because if the even

Exactly. Valuable if you want to ensure the confidentiality of the data no matter what - but you'd better really mean that "no matter what", because if the eventuality arises where the system's properties might be desirable, those same properties essentially spell your own doom. That and the disk-space penalty for the compartments (either fixed or stochastic) meant that, even in areas of potential forced key-disclosure, these systems didn't take off and are as far as I know mothballed and unmaintained.