Mirikon, I direct your attention to the following quotes from various books.
For reasons that may never be learned, the one exposure the Dragon had to the actual Matrix was agnoizing, and left Eliohann teetering on the edge of insanity.
Speaking of yourself in the third person, Cerberus? Perhaps that datajack isn't working as well as it should be, or your time in the Matrix has affected you more than you believe.
- Grier
Neurosis was the name of the decker on [the run that extracted Eliohann], but he died; Ares black IC scorched his brain. Eliohann picked up the Neurosis name and started using it, just like Cerberus. The dragon's got multiple personality disorder - and probably bigger problems - thanks to the chrome in his head. Animals, dragons or not, were not meant to jack in.
- Burning Chrome
[Eliohann] was just a kid - whatever that means by dragon standards, anyway - when he was abducted (by shadowrunners) and turned into a guinea pig in an Emerging Futures laboratory. The early-generation datajack they fitted him with was not without complications, which is a nice way of saying that the cognitive dissonance it caused him drove him insane.
Eliohann became completely immersed in Matrix research, with himself as the primary subject. In fact, he spent so much of his time in the Matrix that it wouldn’t be unfair to call him a junkie. The effects it had on him were severe, and surprisingly well documented. In fact, it’s those side effects that probably prevented Eliohann/Emerging Futures from claiming the bequest in Dunkelzahn’s will. Chances are, he was still working out the kinks and biding his time when Crash 2.0 happened. Anyway, by 2057 Eliohann had already developed the beginnings of a severe dissociative disorder, with symptoms of genuine dissociative personality disorder.
I'm sorry, you were saying? Combine the above with this last quote, and it's pretty clear that Eliohann is a little unstable.
Like so many on the morning of November 2nd, Eliohann flatlined, his mind shredded by the Jormungand virus, leaving behind only a lifeless, comatose husk.
"his mind shredded". "the edge of insanity". "multiple personality disorder". "cognitive dissonance". "drove him insane". Not terms that are ambiguous, are they. Not to mention that according to Plan 9 and the data file he got apparently has "surprisingly well documented" proof of not only Eliohann's actions, but even those of Celedyr himself.
Add in the fact that Cerberus and/or Neurosis have been tampering with AI, black box systems from sealed floors of the damned SCIRE, and the simple truth that Neurosis made sure to tell Plan 9 that Neurosis was the one who provided the data upload on Cerberus and even wanted to be named as the source, and I think there's some compelling evidence to suggest that Eliohann is not entirely himself.
In fact, the data upload on Cerberus goes on to state that "Eliohann/Cerberus seems to have sublimated his draconic nature entirely, embracing his nature as a creature purely of the Matrix". Plan 9 also comments on the fact that Cerberus might not actually be Eliohann, but Cerberus certainly believes he is Eliohann. And we all know what Project Imago, led by Celedyr and his pet "Eliohann", has been up to...
So yeah, I refute your statement that Eliohann is fully in control of himself by the veritable mountain of evidence from generations of fluff indicating otherwise.
I do agree on your point about Eliohann not being Sybil, though. I think there are other forces at work, there. Also, where is it confirmed that PAX has access to such a technomantic ritual? I don't think I've read that story.
[EDIT]
Although his last statement in the Street Legends file does seem damned creepy now that I think about it, especially since it's stated as Neurosis, not Cerberus.
> On the contrary. I’m not that special. I’m here for business, like the rest of you. My rebirth - my current state - changes little. I don’t claim to be the first, and I’m sure I won’t be the last. On a microcircuit board, we will all be born again.
> Neurosis