In a previous post on the "Jupiter-man" variety of Satanic possession (which I surmise is one of Nietzsche-Satan's definitions of "the superman"), I indicated that it CAUSES a "Caesar" or "Roman" mindset. In fact, such a mindset, which Rudolf Steiner attributes to a failure to absorb the Christ impulse (conscience, mainly), "paves the way" for this sort of possession. (So, it seems that the ideal candidates for organized Satanism would be people with a minimum of conscience, such as narcissists and psychopaths.) This is covered in my essay "Jupiter-Man" Satanic Possession, which also states the following:
The preceding excerpt differentiates this mode of possession from the mode by which nature-spirits of destruction, or demons, take possession of a soul. Demons seize control by stimulating "sensuous urges," whereas these "Jupiter men," based on my understanding of Steiner's descriptions, seize control over the person's will and thinking more directly, and have a more purely Satanic influence without the intense demonic drive to torment, torture, injure or kill humans or animals directly, although the influence they have on society can be more devastating.
[It seems to me that someone possessed in this manner would tend to work on implementing the 8th Sphere agenda, since this is Satan's ultimate project. Taking possession of people is a means to this end.]
This position is supported by the following passage from one of Steiner's lectures:
We shall not comprehend the human race without taking these beings into consideration. And these beings, who are, as it were, pushed from behind, for behind them there stands the Ahrimanic [Satanic] power which endows them with their strong will power, which pours into them their directive forces, — these beings who as such are sub-human beings are controlled in their totality by higher Ahrimanic spirits and thus contain something which far surpasses their own nature and being. Therefore they show something in their appearance which, if it takes the human being captive, acts much more strongly, very much more strongly than that which the weak human being can control today, if he does not strengthen it through the spirit. What is the aim of this host? Well, my dear friends, just as the hosts which Michael has pushed down have aimed at human illumination, at human permeation with reason, so these hosts aim at a certain permeation of human willing.
from The Mission of the Archangel Michael, Lecture 5: The Michael Deed and the Michael Influence as Counter-pole of the Ahrimanic Influence
(This is a differenct version of the lecture from which I obtained some of the material for my essay on Jupiter-man possession. The main differences seem to be subtle differences in translation, and the lack of a couple of passages contained in the printed version.)
Taking control of our will-forces would obviously allow Satan to force us to do certain things without our cooperation, so that we would find ourselves doing certain things without thinking about them, and adjusting our feelings and beliefs as necessary to explain why we're doing these things. This is evidently what happened in the Andrea Yates case; methodically killing all of her children was clearly a violation of her maternal instinct, and her insane rationale was clearly intended to cover Satan's tracks by giving the impression that her motivation had originated in her confused mind.