I don't think that there can be a "recommended daytime setting" because, by definition, the recommended settings are what most closely tally to the ISF specs and those are all for dark room. To put it another way, back in the picture tube days if you turned up the contrast too much you would get brownout, which is when the image is so overcharged that it overflows the straight lines, like coloring outside the lines in a coloring book or trying to force 1.4 gallons of water into a gallon bucket. Know what I mean? These recommended settings are how you can adjust your user picture controls to where the result most closely approximates the various kelvins and footlamberts and whatever that are the "standard". The recommendations, therefore, are more scientific, more like video "engineering" and less like opinions. Right? We're not saying "hey, Dave K, you have better taste than me--so how would you set the TV up?" we're saying "hey Dave, you have access to calibration materials and know how to use them, so what can we do to our TVs to make them look professionally calibrated without having to pay a professional calibrator"? See what I mean? "Recommended daytime setting" is almost a contradiction in terms, calibration speaking, since all the source material is mastered to be seen in dark rooms. All you could get would be an opinion, which is ultimately just a matter of taste, and not, as it were, CALIBRATION.
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