I get it. Exposure begins. Depending on the HDRx +Stops exposure value it reads out a copy of the exposure early as the x Channel and then finishes up the normal exposure. That is a better solution than alternating I agree. No weird gaps. But it's certainly different from a normal exposure. Perhaps better. Perhaps sometimes better and sometimes worse. Perhaps always worse. Either way we don't have 18 stop cameras available yet except with unwieldy 3D rigs so wherever it fails we'll be no worse off than we are currently. Where it does work, we'll have something better. Win Win (as long as you didn't assume that HDRx was going to work without any testing and overexposed your normal channel).