apronin has pointed out that devices get into an undefined state when the TPM gets cleared but the disk is not cleared.  We should investigate whether that's happening in the wild.  Do we have UMA?  If not, it might make sense to instrument InstallAttributes::SetIsInvalid() (or one of its callers) to see how often install attributes fail to be verified.

https://cs.corp.google.com/chromeos_public/src/platform2/cryptohome/install_attributes.cc?sq=p:chromeos_public&dr=CSs&l=70