Commentary  Concussions suck. There’s no getting around that. Way back in the 20th century, in my young adulthood, I worked as a land surveyor. I enjoyed being outside and still doing “sciency” things. I learned that I had a knack for adding or subtracting long strings of numbers in my head. Those who’ve done construction staking and grade-setting know what I mean. It became very efficient to just run numbers between my ears without a pen, paper, or calculator while standing in the mud with construction equipment roaring all around me. It also made for fun parlor tricks after work with beers at stake!…