Earlier quoted context omitted.
Depends what you need. Everythin including GI is baked into the mesh. If you want dynamic lights, you could try to bake a out the scene as diffuse and then again as normal maps. Then you can have simplified realitime illumination while still baking in AO, static diffuse lights, and the LODed mesh.
It still doesn't sound like it would work with a lot of direction-depended specular reflections or reflective surfaces.
You could probably bake out normals as part of the process (essentially generate a G buffer) and use that for specular type effects.