Interesting read. I tackled some of it in my dissertation thesis where we examined threat-related attentional biases in individuals with high levels of Autistic and Anxious traits.
From looking at research, it is clear that the psychiatric definition on normality is skewed by diagnostic criteria. When you look at Autism distributions you find that some individuals who score highly (well above the clinical threshold of diagnosis) on measures of autistic personality traits (such as Autism Quotient, Baron-Cohen et al., 2001) you find that many do not meet clinical diagnostic thresholds. Likewise, many who do meet diagnostic threshold do not meet criteria in less-clinical personality-based measures. This issue only gets complicated further by the addition of co-morbidities such as Anxiety and Depression, and what complications they each present.
In many ways, the problems faced by the DSM-V are down to the amount of buy-in that Big Pharma has in defining conditions. It’s much easier to medicate someone for a very clearly defined, categorical condition, rather than arbitrarily examining a case in which someone lies on a spectrum for not one but a variety of conditions. This has led to many seeing the DSM-V as a missed opportunity for a more dimensional view of conditions. In addition to being, in my research, far more encompassing and probably less stigmatising (if it were medically acknowledged that everyone lies on spectra for a plethora of conditions), it is scientifically robust in that endo-phenotypes; namely, attention, gaze, Theory of Mind etc., are more significant predictors than exo-phenotypes that represent traditional medicine. Gaze and attention in particular play immense impact in a variety of conditions it seems.