The only method in which this could work is if some sort of light-mapping system was developed specifically for models. Each triangle in MED would get a flag. If the flag is off (default setting), a smooth gradient is used, like that of gouraud shaded mode. If the flag is on, no smoothing is done and is otherwise flat. Smoothing is decent for curved surfaces and flat is decent for flat surfaces that aren't part of a curve. These flags are only used for lightmap calculations for the model. They are ignored in the engine.