"Unlike other forms of Autism, Aspergers have fairly normal cognitive abilities"

I am not sure what you mean by "normal" cognitive abilities but people with other forms of autism do not always suffer from cognitive impairments. My son is diagnosed with mild autism, sometimes referred to high functioning autism. This basically means he presented with a language delay when younger among other delays. One of the criteria for diagnosing Asperger's (which is no longer a recognized diagnosis and has been switch to Social Communication Disorder in the DSM V) is that the child did not have delayed language....That said, my son and many other people on the spectrum do not have cognitive impairments. In fact, he frequently makes honor roll and just recently got straight A's. It is called a spectrum for a reason.

"which is why people with Asperger's often excel with specific skills in which they show exceptional ability"

This is a stereotype and misconception. While people with Asperger's tend to be of above average intelligence they do not often have exceptional ability with some specific skill. They may excel at a skill just like anyone else with higher intelligence but to say "exceptional" and "often" is a total misconception...unless you have data to back this up?