"Something about it seems like a just-so story. The inherent noisiness of economic evidence is lost, all the graphs are cherry picked to support his view. And yet you'd have to dig quite a lot to find specific things to complain about."
Perhaps your friend could do a really popular debunking book called 'Stop trying to manage noise' and make a fortune? I'm actually a bit serious, so many people do not understand the idea of sampling error and associated noise in data.