Well, we don't know how many 'brain resources' does 'normal' skills that autistic people lack require - and in my opinion they may require as much computing power and memory as Kim Peek's genius skills. We don't know how much of our potential is spent on everyday tasks, like parsing converstaions with other people.

You seem to suggest that the brain is a zero sum game. It may be so, but it is a mere assumption.

I don't have a source for this, but I remember reading about how the "autistic" brain dedicates more of its capacity for more intellectual, rather than using it for social purposes.