- Be aware that the notmuch index is likely sufficient to
- reconstruct the cleartext of the message itself, so please
- ensure that the notmuch message index is adequately protected.
- DO NOT USE ``index.decrypt=true`` without considering the
- security of your index.
+ ``nostash`` is the same as ``true`` except that it will not
+ stash newly-discovered session keys in the database.
+
+ Be aware that the notmuch index is likely sufficient (and a
+ stashed session key is certainly sufficient) to reconstruct
+ the cleartext of the message itself, so please ensure that the
+ notmuch message index is adequately protected. DO NOT USE
+ ``index.decrypt=true`` or ``index.decrypt=nostash`` without
+ considering the security of your index.