Anyone who conjures this defense in Chris's case leads me to believe they are sliding in on the zeitgeist and don't know anything of who he is, what he's said, or what he's done.
You may quibble on definitions all you want, but the path to victory on the back of an insanity defense is more narrow than virtually any other, and Chris demonstrates in almost every way he knows what he has done, he understands and comprehends it, and has dwelled on the nature and substance of the act in enough lurid detail to know it should be both kept secret, and verbosely described to those in whom he confides.
My best advice would be to close the cornell law tabs in your browser and loosen your grasp on this particular straw.