I think there is one more use case for the described technique. I found out that pixels on these LCD screens have some "inertia". That is to say, they turn on and fade off gradually. By switching images very quickly, it should be possible to display more shades. On the attached photo I tried to render 4 shades: ON, OFF, and two transitional colors. One of the shades still flickers, but I think it might be tuned with precise time delays or by switching to a display with different controller.