Hi,
I’m using my iMac with two projectors connected to displayport, but i only using it when i playing stereoscopic 3D games in Windows. To prevent window creation on those projectors, i have to configure very small resolution (120x90@450Hz) with SwitchresX.
Now, i’m only noticed from external displays when i switch to overview grid, so if i can hide it, thats the perfect solution for me.