It was written by someone who posts here in the monitor section from time to time.
As far as his credentials go - you can PM him on his site or visit the facebook page for Savannahmonitors.org and ask him directly. In fact I would recommend a visit to the facebook page:
http://www.facebook.com/pages/savann...18910181506698
Let's just say that there are probably four or five people in this world that I would take varanid advice from (not because I'm that knowledgeable, but due to the fact that many so called experts aren't) - this individual is one of them.