Forbidden to Starve you have no idea what you're talking about.
Personally I thought his post was insightful.
With regard to causes ("genetic" and whatnot), let's keep in mind that like all psychiatric diagnoses, there is no evidence that Apserger's Syndrome even has a common etiology. In other words, there is absolutely no reason to believe that two people who both meet the broad criteria to be diagnosed with Asperger's Syndrome actually have the same underlying condition. This does not rule out talking about Asperger's Syndrome as a construct, but it does mean that there's no reason to believe there is a single "cause", since there's no reason to believe it is one thing.
With regard to your genetic argument, consider this analogy. Everybody I've met who enjoys novels also has a relative who enjoys novels. Therefore, reading novels must be genetic. The problem with this argument isn't that my sample size is too small; it's that I haven't considered people who don't enjoy novels. In other words the prevalence of reading novels might be high enough for my claim to be true without the relative factor being a causal factor. Seeing as the DSM criteria are wildly broad, this may well be the case for "Asperger's Syndrome" as well.
With regard to Asperger's Syndrome itself, it is a classic case of psychiatry acting to pathologise perfectly normal behaviour. The only reason any people exhibit "impairment in social interaction" (to use the DSM term) is that they choose to, and that's not a bad thing. Consider this: if you really wanted to understand "body language", you could easily notice connections between people's gestures and their mood. It's simple inductive reasoning. If somebody were actually unable to pick up on this, it would mean she lacked basic inducting reasoning skills, and her main problem would be that, not "Asperger's Syndrome". The reality is these people are simply uninterested in learning these so-called "social skills", because there's nothing inherently important about them.
What baffles me the most is that some people diagnosed by a psychiatrist with "Asperger's Syndrome" choose to embrace it as an identity. The diagnosis is basically an attack on your interests and your choice of what to prioritise in life. If we want to celebrate differences in personalities, let's come up with a movement with no psychiatric baggage.