I hate to say it but there could be a whole lot in common between ASP and a least certain subtypes of "Borderline Personality Disorder".
Before I get into this subject though, first of all, I feel there's a real need here to point out that "manipulative" is not part of a diagnosis for BPD. Anyone who has worked with this population will find that it is precisely their lack of communicative skills, their inability to clearly express their intense, overwhelmingly inner emotional pain, that has made them seem "manipulative" in the past. However those who suffer from pure BPD generally lack the foresight and planning that true manipulation would entail. That said, very often those with BPD who are not autistic have an astonishing capacity for empathy whereas those with ASP generally have great difficulty in "putting themselves in someone else's shoes" - as hard as they try. (Which would also mean that they are not capable of "true manipulation" any more than someone with BPD, albeit for other reasons). Many BPD sufferers cannot shut out the suffering of others. One could say that they have no skin - they are constantly assailed by the emotions of others and cannot filter out other people's pain from their own. This alone drives many of them to isolate themselves over the years.
The DSM description of this disorder mixes all kinds of states with traits and does not achieve a coherent description of one kind of personality. It is becoming more and more clear that there are many subtypes finding their way to this diagnosis. Perhaps the most important subtype for this conversation is the "internalizing dysregulated borderline". These are people in intense emotional pain, mired in negative feelings, most often dysthymic, who do not think in black and white, but who spiral down into prolonged periods of anguish, fear, guilt, shame, etc. (intense dysphoric states), tend towards major (melancholic) depressions, are mostly introverted and are very far from the stereotypes of this disorder as reflected in these posts. They are almost invisible, as they had great difficulty in expressing any feelings of anger whatsoever - turning anger against themselves repeatedly - they may be masochistic and very SELF-destructive, undermining all their chances for real achievement.
This subtype is most likely to be classified "fearful-avoidant" as far as attachment goes. They are the most likely to spend years of their life "dissociated" - i.e. numbed out, feeling little or nothing, barely "alive" emotionally. They often have the similar stories of peri-natal traumas found in many bios of those more clearly in the "autistic spectrum". They often present with speech difficulties and feel cut off from contact with others just like those with ASP. It is very likely that many people with very difficult childhoods and adolescences suffering from ASP are unfortunate enough to also fall into this subtype of BPD.
Over half of those suffering from BPD are not related to the impulsive-histrionic spectrum of this disorder, but rather to the "emotional dysregulation"- dysphoric spectrum. There is more and more speculation as to the possibility that these are even two separate disorders.
Emotional dysregulation also includes the lack of nuanced emotions - one can swing from feeling nothing at all to writhing under intense feelings of self-loathing, guilt, shame, etc. in a flash, but hardly with anything in between. It is thought that the HPA axis is damaged - their nervous system in on red alert, and insomnia is rampant among these people.
It is quite possible that in these individuals BPD is a kind of childhood PTSD, possibly with roots in the first days/weeks of one's life, which would make it a developmental disorder, and link it to other developmental disorders such as found in the entire autistic spectrum. BPD and ASP are both disorders of the SELF. It is this sense of self that is so hard to obtain for individuals on the autistic spectrum and so hard to maintain for those who we call "borderline" (for lack of a better word). One can say that without a firm sense of self, one cannot have more than a vacillating sense of others...
It's time to stop thinking of BPD as a kind of personality, all the research points to problems with emotional processing in some, with impulse problems in others, with both in still others and as BPD makes it's way slowly and surely to AXis I (as did autistic disorders before it), it will become more and more evident that even those with ASP can also suffer the hell of being "borderline". Once we stop using BPD as a lame adjective for difficult or unlikable people, we will finally realize to what a degree all kinds of (good, caring, sensitive) souls may have this disorder, even those with ASP. The "quiet" ASP who also struggles with the nightmare of this inner pain merits the same compassion and attention as that of more "extroverted borderlines".