"One thinks immediately of the autistic savants who have perfect memory of all the events of their life, including eidetic images of every page of every book they have looked at.

It emphasizes how pitifully little of our brains we utilize on a regular basis."

I love this myth that we don't use the considerable amount of our brain capacity. Abstract thought of even the most basic sort is the result of the carefully controlled cooperation of numerous disparate regions of the brain. Our brain don't just have huge dead zones.
As for this romantic idea of the autistic savant, it's also silly. The normal human brain receives and processes a massive amount of data every second. It discards the input it deems irrelevant and focuses on the most important. If it didn't, you would be overloaded constantly with trivial, distracting information that impaired your higher functions. This is essentially what disables the autistic. While they may like Temple Grandin be geniuses about very specific topics, they are unable to function on more abstract levels such as comprehending social interaction.