It seems unlikely that (a) FBI understood truecrypt (b) the target understood truecrypt (c) the target misunderstood the entire purpose of truecrypt, and the

It seems unlikely that (a) FBI understood truecrypt (b) the target understood truecrypt (c) the target misunderstood the entire purpose of truecrypt, and they would misuse it to expose themselves and (d) the FBI expected this and intentionally blew their cover, leaving the target a chance to destroy the drive.