It looks like a lot of those effects are possible because when outputting to composite, the horizontal rows are well-defined, while the vertical columns are not

It looks like a lot of those effects are possible because when outputting to composite, the horizontal rows are well-defined, while the vertical columns are not and unlikely to precisely match/map the output. For instance, there are a lot of clean gradients from top to bottom (clean rows of color) which use dithering in the rgb output. Columnar gradients would have bleeding/blurry edges due to the unpredictable nature of the analog display. Am I understanding this correctly?