Drew Ryun seems to be choosing his experts by finding which ones agree with what he wishes (or believes) were the case. As a non-scientist, he knows he can’t assess the evidence itself, and he has to trust someone. As a scientist with training in some of these issues, I can evaluate some of the claims on my own, but even I have to rely on experts. It gets me nothing to choose my experts in a biased way, I would rather find the scientist(s) most likely to be right. Within the range of existing scientific opinion and evaluation, most of the views are likely to cluster around a certain point, based on their expert knowledge of the evidence. That point may not represent the true state of affairs, but it is the view that is most likely to be right. Choosing an extreme that I agree with is no more reasonable than choosing the opposite.