> Another feature about this guy is his low threshold of boredom. He'll pick up on a task and work frantically at it, accomplishing wonders in a short time and then get bored and drop it before its properly finished.
> But brilliance is not enough. You need application too, because the material is harder at university. So pretty soon our man is getting B+, then Bs and then Cs for his assignments. He experiences alternating feelings of failure cutting through his usual self assurance. He can still stay up to 5.00AM and hand in his assignment before the 9.00AM deadline, but what he hands in is not so great.
That linked article is literally just describing undiagnosed ADHD, which yes, can affect otherwise successful students (of which I was one). Usually it's a form of Primarily Inattentive ADHD: https://en.wikipedia.org/wiki/Attention_deficit_hyperactivit... , which doesn't present as hyperactivity but instead as inner restlessness.
Teenagers with this variety of ADHD go undiagnosed at significantly higher rates than Hyperactive ADHD. Those with the hyperactive variety are easily noticed due to their tendencies to run around rooms, act out, jump out of their seats at inappropriate times, and so on. But the Inattentive kids suffer due to the existence of just this very stereotype -- the smart but bored kid. For some reason, with ADHD-H we're able to say, "This kid isn't following the norms in school because of a cognitive deficit," but when it comes to ADHD-PI people think "This kid isn't following the norms in school because he's just so over it, man."
Meanwhile, these kids are often tortured by their inability to work as hard and as consistently as they want to. Everyone in my life just assumed for me that I was "so smart that I was just bored in school, no challenge!", but meanwhile I was depressed from about the age of 10 by my complete inability to succeed in school to the extent I wanted to. I loved school, and was depressed by my inability to pay attention and work harder.
These students were able to succeed in high school because the material is mostly accessible via some amount of common sense. I was able to ace a lot of objective (multiple choice, etc.) exams through nothing more than logical deduction. But in college, assignments require more discipline over time -- writing long research papers, motivating yourself to work on something over weeks -- which is when the failures start appearing more and more frequently. My GPA went from 4.0 in middle school to 3.7 in high school to 3.2 in college. 3.2 sounds fine to some, but it was the most depressed I've ever been because I felt my life's potential slipping through my fingers.
So rather than having professors write condescending articles over our "bipolar personality" I'd much prefer if we, as a society, could work to truly understand the challenges that these kids face; to look beyond the stereotypes and actually care about their wellbeing.
 I used to think ADHD was made up. Why? Because I couldn't understand what was different about kids with an ADHD diagnosis. I would read lists of ADHD symptoms and think, "But that's just normal life! I experience that stuff all day every day, and I don't have ADHD!" It took me until the age of 28, and until my wife was there to help me shake the cobwebs off of my denial, before I was able to have the realization that strongly relating with the ADHD symptoms meant that I had the disorder, not that ADHD was "just normal life."