There are two things we want to learn when it comes to testing a game in stereoscopic 3D. The first is all about quality, and we want games that can offer an error-free 3D gaming experience, without being forced to turn down graphics settings.
It's often the case that PC games in 3D are plagued with visual anomalies, and the only way to get rid of them is to turn down graphics or "eye candy" settings like HDR lighting, shadows, reflections, and shader levels. While all games begin with a perfect score of 100%, they get deductions every time a special effect has to be turned or forced off by the user or driver developer - and if there are visual problems that remain despite the gamer's best efforts.
The second part of the score has to do with visual flexibility. Many gamers are content with a depth-only or "100% behind the glass" 3D experience, while others would like a combined depth and pop-out effect where things can seem to reach out and pierce through the display's screen. While this isn't a qualitative score, results need to indicate a game's visual flexibility and under what circumstances.
Whether or not gamers like a combined depth and pop-out experience in their titles, it's an important part of the test process to ensure that game anomalies are in check, and the game's flexibility is accurately indicated.