Some very good points here. It's funny that some of us are trying to analyze all this and considering multiple possibilities,
It's called "Ochams Razor". The simplest explanation is the best explanationYou will consider any explanation no matter how imbecilic, and ignore the obvious explanation
Dan was asked to review many coins, and so he reviewed HAL.
Some how you want Dan to be merely a reviewer of all the other coins but suddenly, when it suits you, he stops being a reviewer and becomes the developer of HAL.
http://en.wikipedia.org/wiki/Occam's_razor