You can still switch your focus with these because you still see the real world. However it is true that the objects are rendered ("OpenGL-like") the same way no matter where the object is located in the scene, so while it gives you the feeling that you can focus your eyes on the object (because of their 3D position and the tracking), the objects always appear "clear" which can be annoying. That said, using them 8 hours must be hard : the virtual objects emits unreal lighting (different and stronger than the light reflected by real surfaces)
