Aren't the "sustained luminance" values not actual physical limitation of what the display can output in a sustained manner but what the manufactures arbitrarily cap the displays at so as to meet their desired longevity under normal use (due to unavoidable OLED degradation over time)? So the stated peaks of 1000 nits could be sustained full-field but doing so would just lower the life-span on the display way below what is acceptable? Because if so, and assuming near linear degradation vs. sustainable luminance output, they could just set the display to output full-field 1000 nits but with BFI at 20% on-time and achieve the same average luminance output effect as 200 nits full-field sustained.
Though I've yet to confirm so only an assumption, seems to be what Philips are doing with their OLED+936 to achieve BFI without much brightness reduction vs. BFI off. I was tempted to go for it until this Alienware was announced making me willing to hold off from going OLED BFI a bit longer until the display sizes are more monitor friendly.