Aspergers syndrome is quite remarkable to say the least. The fact that a child with this illness doesn’t have any sort of cognitive delay before the age of three is astonishing. These children begin their childhood with the “normal IQ.” Aspergers children tend to have poor social skills and have very few friends. An intriguing and unexpected fact is that they have been known to be clumsy and awkward. Hand and eye coordination isn’t a strong point for them but they do no have to have every symptom to be diagnosed. In a website named "NAMI," many side effects and symptoms are stated. One sided conversations are common especially when it is about something the child is interested in. Difficulty in managing stress and having possible meltdowns is also a symptom. National Alliance in Mental Illness can be a great read for a better understanding before heading to a doctor for possible diagnosis!
What makes this response dangerous is that some parts of it are true (or at least can be true of some people on the spectrum). However, there are some issues that are glaring to anyone who knows better.
The idea that Autism is a disorder that results in low IQ is outdated and based on the results of tests given in ways that some of us can't handle. Autism is in large part a communication disorder. One of the biggest common issues is our difficulty communicating with neurotypicals.
It's kind of like an American visiting Australia. Technically, they speak the same language, but the dialects are so different, that understanding is not only not guaranteed, but the chance for misunderstanding is quite high.
So, you can be the smartest person in the world, but if you can't communicate it, then others won't be able to see that.
That's what researchers have slowly been realizing, thankfully. Even those who are "low functioning" are typically of average intelligence and show similar ranges of intellect as any other population. It was the tests that were failing to allow them to communicate that.
Additionally, one of the hallmarks of Asperger's compared to classic Autism is that things like speech delays are not typical. There is also quite a bit of crossover between Asperger's and gifted.
That said, regarding the original questions: Asperger's is a syndrome, which by definition means that there is a list of symptoms that are common among those with the syndrome, but a given individual will have only some of the symptoms, and the severity will vary, as well.
Technically speaking, the symptoms that one has are there all the time, but because many are related to communication, we can often hide them to a point. For example, small talk doesn't make sense to most of us and doesn't come easy, but through practice, some of us can engage in it for a time. You've seen this behavior with your son and eye contact. For many of us, eye contact is another thing that doesn't come naturally and makes us uncomfortable, but with practice, some of us can do it for short periods of time, or behave in ways that make our lack of eye contact less apparent.
As for friends, friendships in school aren't uncommon, but they might seem shallow or otherwise unusual to the onlooker, because they often revolve around a shared interest and little else. As we reach adulthood, friends become harder to come by, but still not impossible. The difficulty can also be compounded if we've been bullied and/or betrayed in the past. I've found that interest groups help open the door to at least casual friendships, so things like meetup.com are quite valuable.
That said, Asperger's isn't something that needs cured, and it's not the end of the world of he does get diagnosed. What it does mean is that he would do well having someone he can trust to help him understand the nuances of social expectations, and someone with the patience and awareness to realize that what's extraordinarily obvious to most people may not be to him, even if he's smart enough to get into Mensa.