That said, it's important to point out that the author of this post is defining ADD differently than the medical definition of ADD. The idea of hyperfocus is very popular among the self-diagnosed and on internet forums dedicated to ADD, but the term "hyperfocus" doesn't actually appear in any of the medical literature I can find, with the exception of a few books that seem to suggest that "hyperfocus" is more likely related to the idea of perseveration, which is a deficit in set shifting ability. However, perseveration isn't as selective as the concept of "hyperfocus," which seems selective for enjoyable tasks.
The idea of hyperfocus as a component of ADD is part of a bigger problem: The modern pop-psychology definition of ADD has been watered down and expanded so much that it is beginning to feel more like a horoscope than a medical diagnosis. Even official medical diagnostic criteria can't seem to agree on how strict the definition of ADHD is. For example, ICD-10 ADHD diagnostic criteria will yield a rate of roughly 1-2% ADHD in the general population of children. Using the DSM-IV criteria, that number rises to roughly 6-7% of children.
However, if you have the average person read an internet definition of ADHD or follow one of the first results for "ADHD test" in Google, you'd be hard pressed to find an average college student or tech worker who wouldn't identify as at least mildly ADHD per the pop-psychology definitions. Take a look at one of first results in Google for "adhd test": http://psychcentral.com/quizzes/addquiz.htm
Questions such as "How often are you easily distracted by external stimuli, like something in your environment" are so vague as to be applicable to everyone who has ever been distracted by a notification on their phone. I don't think I've known anyone who wouldn't agree with questions like "How often do you have difficulty sustaining your attention while doing something for work, school, a hobby, or fun activity" when we're expected to sit through 8+ hour desk jobs doing things that frequently aren't tasks we would have chosen to willingly pursue.
The growing misconception seems to be that for a non-ADHD person, it should be easy or somehow enjoyable to focus on the things that we don't necessarily enjoy doing. That's obviously not the case, but these casual redefinitions of ADHD as a disorder that is accompanied by an increased ability to focus on enjoyable tasks are really stretching the definition of what it means to have AD[H]D.