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A "simple" PAL receiver does not have the delay line that produces electrical averaging of successive lines. Don't know if any simple PAL sets are made these days. This would be like the early NTSC xperiments with alternating phase, and depends on the human eye to do the averaging. Eyeball averaging is not perfect, and the resulting effect was known as "Hannover bars" in honor of the home town of Walter Bruch, PAL inventor.
On another note, there is a classic paper from the NTSC color development days on why a tint control is needed even when there is no variation in phase (to compensate for the particular red/green color mixing characteristics of the viewer's color vision). The variation of red/green ratio to make flesh tones is actually considerably larger than the smallest noticeable difference, even among "normal" viewers that would not be considered to have a color deficiency. However, since there are typically more than one person using the same TV, a single tint setting that is a compromise for everyone viewing is most practical, and it might as well be the "standard" one that PAL and NTSC use. Viewers with normal vision will find the result acceptable, although not an exact match to what was in front of the camera. Note also that the really proper adjustment for an individual's color vision involves the complete color matrix of 6 values, i.e., gain and phase for each of the three color-difference signals. Adjusting the tint can correct the flesh tones for viewer differences only at the expense of throwing other colors out of whack.
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