I wonder about that too. Too plead NGRI would acknowledge his mental illness. Unless he claims self defense, blaming his parents for provoking him isn’t going to prove he’s not guilty of murdering them. At best that could reduce his sentence after he was found guilty by introducing mitigating circumstances.
Self defense wouldn’t surprise me but if it can be proven one or both were in bed when he attacked them, that would be a tough sell. If not that, I think he’ll drag out this pretrial phase as long as possible, then plead guilty. He’s lost his control, nothing left to empower himself with. Representation by a PD, the same as other destitute accused men and women, is likely bruising to his ego.
JMO