Applications that are really doing multithreaded 3D rendering are quite rare (and the only case I know is just starting with one thread and then moving to another while not using the previous one again).
Empire Earth does, contrary to the first impression, more than that. It switches the threads at least 2 times when trying to start the in-game engine.
I'll stick to Half-Life and Need for Speed 3 for my D3D7->WineD3D work ;-) Hopefully these apps aren't multithreaded too.
Stefan