[ajarmst]

The author has a pretty good CV, but as his Wikipedia entry notes, there is a concerning history to some of his publications. The WP entry cites several expressions of concern, which are worth a read. See, in particular, the note at the link below from Retraction Watch (one of the better sources for checking a researcher's bona fides):

Researcher who threatened Retraction Watch with lawsuit corrects funding source for several papers (https://retractionwatch.com/2013/10/17/researcher-who-threat...)

The argument made in the article seems well-supported, but I'm not competent to evaluate it. Given that this is an un-reviewed letter to the editor from a single (albeit apparently quite well-qualified) researcher, I'm going to wait for more (peer-reviewed) evidence before trying to form an opinion.