For a more user-friendly tool, take a look at CogTool. You can build or import a prototype UI, create tasks (sets of actions: click this, type that), and let the software evaluate or automatically optimize the interface. Last time I checked they used ACT-R as the cognitive engine, so the results should be accurate.
For actual design decisions, I'd much prefer a method that has developed for thirty-some years, is based on actual cognitive models and has been empirically validated.
Besides, it's not that difficult to use. Building and testing your interface in CogTool would take you about an hour the first time, but it is easy to learn. You can even import HTML and record your actions. The results are pretty accurate, and you get automatic interface optimization (e.g. on widget size, location, types) too boot.
So, the author had a nice idea, but it has been done already. (At least for the user testing, the accurate results, the "codification" and the books; I don't know about the consulting company.)
