Sorry for the late answer, but I’d got a lot of work.
So, I made some test and it seems when you turn On the Ultra Motion Clarity the TV display switch a lower, decreaded resolution. It maybe about 3840 x 1440 pixels or 1440p.
You can see the differences on the pictures.
As you see at the last picture the 1 px horizontal lines is not separated in UMC ON as in UMC OFF.
And the colors, the contrast of the video is worst then UMC ON.