I accidentally gave it a no vote (figures, my first one ever on this site!) because I thought oyamafamily had put it the difficulty switch in the B position. That was his earlier score, which I didn't read all the way down in his paragraph explaining all of his scores until later. I've since rewatched the video from the point where he put it in the A position, seeing that it was indeed changed to that, plus at one point where his chicken got hit, it reappeared at the very bottom of the screen, confirming the switch was in the A position after all.
An impressive run, by the way. Even though the game goes by set patterns with the traffic, you still have to be extra careful with using the left chicken. Most of us would probably prefer using the right one.