In the case of Smart Contracts, there are self-destruct functions for the contract which can only be run by the contract owner. In many cases attackers have found a way to take over the contract owner. Would it be possible to place an encrypted blob along with the public key and original plain-text message in the smart contract? Then at time of required authentication (when the true author wants to destroy the contract) the original private key could provided for authentication. Is there any crypto flaw in this?