If I were to specifically attempt to identify unusual behavior, then I may be able to do so correctly, but I usually do not pay enough attention to people to note how unusual or usual their behavior is. Of course, when the fellow residents of this dorm hall decided to make loud noises (sometimes involving animal noises) at odds hours of the night, I usually notice if I happen to be awake.
I usually explain it as this: unless you're walking into a business meeting in a clown suit, I am probably not going to notice that you're peculiar, and, even then, I would attempt to judge it from a purely intellectual viewpoint (I wonder if he's trying to boost morale...maybe his presentation will utilize this?).
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I am not a textbook case of any particular disorder; I am an abstract, poetic portrayal of neurovariance with which much artistic license was taken.