It would be interesting if the driver could sense whether the pixel had fully transitioned or not, allowing it to measure transition time and accurately generate greys.
I have no idea whether it's feasible, but having a direct feedback mechanism would be pretty awesome.
I was thinking some kind of current monitoring on the line. Surely there's some difference in draw when transitioning versus fully transitioned.
But if a display only officially supports black & white, its driver just needs to know the duration of the slowest transition across the operating temperature range. It could then use that duration for all transitions, regardless of the temperature.