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Here's an example - look at the differnce between the vertical and horizontal strokes of the letter t in Beatles. Unfortunately, I can't turn off the dot crawl in this simulation, whihc would be less visible in reality due to alternating phase from frame to frame. The dot crawl (with a simple chroma trap in the luminance) will generally fall in the same area as the red-orangish discoloration of the yellow.
It should also be visible in the vertical vs. horizontal strokes of the B. I find I have to zoom out quite a bit, until the image is about 1.5 inches wide (at about 15 or 20 inches viewing distance), before the discoloration becomes really less noticeable. This shows that the ability to get away with less chroma bandwidth than luma and use narrower Q bandwidth than I, does not have a sharp dependance on viewing distance, but also depends on the viewer not having an original to refer to. When home computers came out however, the lack of chroma resolution on small text and artificial objects with edges but no texture and possibly little brightness contrast made the failings of composite video obvious.
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