No offense, but that theory is nonsense and I doubt that the author did proper research on the topic.
Age of Conan failed because at the time it was filled with a two or at max four weeks of content and that was it. The gameplay totally changed after the first 20 levels, from a deep single player action-adventure - which was alot of fun in the vein of Oblivion and The Witcher - to a dull and empty game with no content.
ALSO: Promised features that didn't make it into the release version.
I fell in love with this game and bought it BECAUSE of the demo and I still feel betrayed by Funcom.
Basically what the author is suggesting is, that a small taste of something good makes us don't wanna eat more of it. Makes no sense and is not human nature.