...Projective telepathy?
Psionics are definitely part of both githyanki and githzerai culture. How do githyanki feel about members of their own kind who manifest telepathic powers -- specifically, the ability to telepathically dominate and manipulate others? (I'm looking specifically at the telepathic specialization for the Psion class here.)
I can see several takes on this:
* Maybe the illithids actually were successful in breeding the capacity for projective telepathy out of them, so (full) telepaths are very rare.
* Githyanki are so paranoid about psionic enslavement that they kill their own young who manifest strong projective telepathic abilities. (Possible, but githyanki *really* dislike killing others of their own species.)
* Projective telepaths exist but are very much distrusted, and possibly placed outside the usual order of command. (Are you sure you want a supreme leader or other commander who is capable of turning the minds of his subordinates inside out?) They might also be expected to have a certain style of dress, tattoo, symbol, etc., making it obvious to other githyanki what they are.
* Projective telepathy is treated no differently than any other weapon or skill. (I see this as a bit unlikely. Seeing someone else being directly mind-controlled would probably be deeply disturbing to any right-thinking githyanki, seeing how it personifies everything that they've been taught is evil.)
* Regardless of whether telepaths are viewed as 'normal' or not, they probably are highly valued as illithid slayers.
* It seems likely that (generally) they are forbidden from using their powers in a hostile manner against other githyanki, but permitted to use them against any and all outsiders.
Would psionic probing be permitted against a githyanki accused of treasonous activities, or is the cultural abhorrence for such things so great that it would not normally be used? (Additionally, can they really trust the psion?)
Not that I'm endorsing this option above the others, but to work the kinks out:
Githyanki who display an affinity for projective telepathy give their family-units honour by having a private audience with the Queen. (They are, incidentally, never seen again.)
Pants of the North!