What is the role of neuropsychological testing in ADHD?

As discussed on another page on this website, neuropsychological testing should not be ordered to diagnose ADHD or to rule out the diagnosis of ADHD. What then is the (limited) role of neuropsychological testing in persons with ADHD or possible ADHD? We need to know this in order to know what tests to request–“neuropsychological testing”…