Unwise, and I expect he will get his head handed to him during trial.
His comments are very revealing. In effect he acknowledges that the government has no interest in criminalizing even the knowing transmission of information about a person with classified status (because there is no law against it), and he admits that his investigation of the facts cannot lead him to conclude that Plame was covert.
There is no interest his prosecution is vindicating - none on the facts or the law - relating to the release of either classified information or the identity of a covert agent.
His words speak for themselves.