No, he's saying that if you "reverse the movie" of the ball accelerating down the inclined plane, then it will appear to decelerate as it rolls up the plane; lo

No, he's saying that if you "reverse the movie" of the ball accelerating down the inclined plane, then it will appear to decelerate as it rolls up the plane; looking at a ball slowing down as it rolls up a plane you can't tell if time is going forwards or backwards.