I agree with everything you say, although my own experience with PTSD has different idiosyncracies.
I believe it could be said in general that PTSD is maladaptive. But Jodi is nothing if not adaptive; she's a veritable chameleon. She's even, by all accounts, happy as a clam in jail (I'll bet she is, too, since it fosters her sneakiness.).
There's no evidence in Jodi of intrusive thoughts, creepy feelings, hallucinations, inexplicable fears, avoidance, acting as if at a prior trauma. She hasn't to my knowledge even spun lies that would indicate she was experiencing these features of PTSD, like: What exactly does she avoid? What shows up in her dreams? What aromas bother her? What is going on when she is startled? What kinds of things has she imagined that were not there?.....
I don't believe Jodi dissociates, either. It's more like she's not on the ball, and this happened because she spent her days obsessed with men who did not (or no longer) want to be with her. Plus, she's never been a focused kind of a gal, fixated on men, maybe, but not focused. The messy crime scene is testimony to her lack of focus: not lack of planning, but disorganized follow-through. That the crime scene happened is, of course, a sign of her fixation. None of this at all qualifies as "dissociation."
And, to use an example from today's testimony, if Travis truly had his hands around Jodi's neck, that would have been a typical spot to dissociate. For instance, I might not even be able to process what was happening, I might not notice pain, and I might be in a stupor. But what does Jodi do? The opposite! She galvanizes her no-doubt-newly-manicured fingernails into action, contemplates whether or not to scratch him in the eyeballs, and decides not to as a matter of selflessness. This one sentence amounts to about 5 examples of being fully present.
If Jodi were really a PTSDer who once experienced a man's hands trying to strangle her, she should by rights, these days, be having all kinds of nightmares about hangmen's nooses around her neck....
And I don't believe you could get PTSD if you're the aggressor; you get PTSD from a feeling of helplessness. It's not even possible, in other words, to get it during a murder you are committing. No way, I'm thinking. In Jodi's case, she was doing fight and flight, the opposite of helplessness: she stabbed, shot, galvanized herself into action on the cleanup, and fled.
As an aside, the whole "I am in a fog about the murder" echoes the excuse of another murderer Juan prosecuted (put on death row?) successfully: the guy who claimed he was sleep-walking when he killed his wife. Yes, Juan has been through this schtick before......