I'm not sure I'm willing to give her the Yates benefit of the doubt yet.
She was mentally ill, yes. So are a lot of people in this world. I suffer from OCD and depression, but that doesn't make me insane. I know when I need help and it sounds like she did, too. The McNaughton Law only dictates that a defendant know her actions were wrong at the time and it seems clear she did know. This was premeditated in a pretty intense way.
I think her mental illness augmented pent up rage and resentment at giving up her career for the kids and she was unable to deal with what sounds like teenage rebellion. Calyx and her father had already agreed she could go to boarding school, presumably in an attempt to get away from her mother. It sounds like Calyx was a bit of a handful, but they probably fed off each other's hostility. By all accounts, Calyx was a go-getter and an angel at school.
The post-it notes are truly something. I'm struck by the neat handwriting and the fairly lucid grammar. No sign of the tardive dyskenesia in her writing. To me this all sounds like a woman burdened with life and kids and probably angry that she was doing it by herself.
A lot of people assume she is seriously mentally ill because of the tremors after her arrest, but she also has Parkinson's disease.
Maybe she was overmedicated and those medications interacted with each other, but I think to assume she's mentally ill is an easy out for her. It sounds like she had enough with what she deemed to be mouthy and rebellious kids, went out, bought a gun, and chickened out before she could off herself. I have no doubt she was in a bad mental state, but does that matter if she knew what she was doing was wrong? If she was lucid enough to write post-its and stick them on the objects of her malcontent, can we say she was too far gone to think "Maybe I shouldn't do this' and walk away?
I have extreme sympathy for someone like Andrea Yates who was truly psychotic and showed signs of altruism in that horrible murder. This case just shows a woman who had the foresight to go out and buy a gun days in advance, send emails to her family, and then execute her children after writing out the reasons why. I want to see her tried and not immediately chalked up as another poster-child for mental illness awareness. I think ANYONE has to be somewhat mentally ill to kill another human being. But insane?