I can't tell from that one, but I think it could possibly be one of those jackets (forget the name) that does drape properly with both buttoned. That actually seems fairly likely, given that he has a "following." Most people who are interested in menswear know not to button the bottom button.
Incidentally, he looks sort of dumb, bottom button done or not. The pants aren't my thing. Also, I would say that comments like this directed at a style blogger are entirely appropriate. I wouldn't say he looks dumb to his face, but the internet is not a hugbox, and I think there's less of an obligation to be gentle with someone who puts himself forward with confidence, saying "this is good," than there is with someone who's just asking for advice and information.