> In light of this research, permanent winter time would be good for health and economy. Permanent summer time will be worse.
Only one of these papers (the researchgate one) actually asserts a hypothesis for the root cause of the correlation observed that might (but see below) make this true--later time of sunrise. The others all assert the hypothesis that being further out of sync with the rest of your time zone (which determines what one paper calls "social time") is the root cause. The way to fix that is not permanent winter time but narrower time zones--for example, a good chunk of what is now the Eastern time zone in the US is closer to the Central time zone meridian and should really be in that time zone. But that fix is orthogonal to the permanent summer time question.
Unfortunately for your argument, the one remaining paper (the researchgate one) is looking at variation with latitude, not variation with longitude. Latitude variation is going to be there regardless of what we do with daylight savings time. The fix for anyone bothered by the researchgate paper's findings is to move further south.
Only one of these papers (the researchgate one) actually asserts a hypothesis for the root cause of the correlation observed that might (but see below) make this true--later time of sunrise. The others all assert the hypothesis that being further out of sync with the rest of your time zone (which determines what one paper calls "social time") is the root cause. The way to fix that is not permanent winter time but narrower time zones--for example, a good chunk of what is now the Eastern time zone in the US is closer to the Central time zone meridian and should really be in that time zone. But that fix is orthogonal to the permanent summer time question.
Unfortunately for your argument, the one remaining paper (the researchgate one) is looking at variation with latitude, not variation with longitude. Latitude variation is going to be there regardless of what we do with daylight savings time. The fix for anyone bothered by the researchgate paper's findings is to move further south.