Strictly speaking, a pulse mechanism doesn't really add much lag, if any at all, so long as they're not coupling anything else with it. Interpolation sure does though, as well as any other computation centric hoo-hah.
There have been cases where people have used "MotionFlow Impulse" on the higher end Sonys in game mode (everything else shut off). It works, and works well. There's not much (or none at all) bandwidth footprint in merely pulsing the light.
Here's Mark Rejhon's explanation of it.
Thanks - that is the same point I was attempting to make but you beat me to it and stated it much more clearly...
p.s. but if alwayssts really needs 600 Nits of output brightness, he can probably forget about activating the scanning backlight (and hopefully has a good pair of sunglasses )