Doesn't make sense to me. Lots of gifted people have lower (more average range) working memory scores without having ADHD.
Moreover, I've had conversations with Dr. Lucy Miller of the Star Center (OT place specializing in SPD) and neuroplasticity is the reason the brain can still set new pathways - the very reason that OT can make a difference - but it is believed that there is less neuroplasticity as one gets older.
Neuroplasticity is what would allow the problems in the brain to get fixed. If the brain already had developed a work-around to the problem, there wouldn't be much of a problem left, or would there?
My understanding is that ADHD can indeed involve very good focus at certain times - hyperfocus - not necessarily that one can never ever have good focus. I guess I don't really know but it doesn't sound right to me. You might find the chart at the end of this link interesting
http://www.visualspatial.org/Articles/george.pdf
