It's simple: it is the only book I've turned every page without retaining anything. Indeed, every "game" (as defined in serious games) is explained by a weak story (really stupid). So that: 1) You read pages and pages of 1 poorly told story. This story is meant to explain the game, but suddenly you understand metaphors and complicated ties the actual structure of the game ... 2) As a result, well structured and written in good French, you FINALLY readable prose that explains banalities as how this game is powerful, when to use it, etc ... It's a shame, because the used games in vocational training are formidable. I do not understand the bias of the authors.