He hasn't used stats he's misused stats. He compares a corner with a pass from a keeper to a defender or a back pass to the keeper.Here's an article that completely flips around the a thumping that there not valuable
http://www.businessinsider.com/value-corner-kicks-football-2013-7?IR=T
Again it could be complete cobblers but he has used stats
With thinking like that I'm surprised he managed to tie his own shoelaces, let alone write an article.