Thanks for the really extensive discussion of my question regarding Daylight Saving Time.
To put it into context: Whilst most modern operating systems can deal with DST changes without issue, it is partly the interconnectivity through the Internet, and update servers and software relying on this, that can still occasionally run into problems here. Just before my tweet to you, I lost several hours of updating a PC, that failed because of time stamp incongruence.
Now to chime into your discussion: I am located in the east of Belgium, so more or less on the same geographical latitude as the southern Provinces of Canada, and I am definitely familiar with the issues of pitch-darkness when leaving for school/work in the morning and coming home in the evening.
As you mentioned, DST was implemented in the early decades of the 20th century, and became heavily utilised due to the energy crisis of the 1970s. It is an arbitrary system the we invented to make the most use of natural sunlight after society moved away from being entirely dependent on it. Whilst the actual energy savings from switching to DST are questionable, as per Marla Desat's example of Indiana, I feel we have since then created enough measures to save energy in our daily lives, that are independent of available daylight. Just in terms of lighting, the availability of LED, energy-saving bulbs, etc. have made more of an impact than switching back our clocks an hour for summer.
Additionally, as a society we have moved away from the rigid work structures that were employed at the beginning of the 20th century, and with the advent of sliding hours in the workplace, dealing with the change of the seasons is becoming more a matter of personal scheduling, rather than a convention we need to adhere to as society. This is especially true since a majority of the world no longer observes DST (DST Map [https://en.wikipedia.org/wiki/Daylight_saving_time#mediaviewer/File
aylightSaving-World-Subdivisions.png], Source: Wikipedia).
In terms of health effects, I think we also forget that there are also natural ways to deal with the change of seasons, starting with fruit and vegetables rich in Vitamin D (mushrooms as well) becoming available as winter approaches. And lets face it, our planet does not care one bit if our clocks say 7h00 or 6h00 when we get up in the morning, but it is just as much affected by changes in natural lighting and temperature as we are. We have perhaps lost sight of this as certain produce have become available all year round.
Perhaps the most frustrating aspect is that as a global and interconnected society, we can no agree on one system to work with. Perhaps it would not be as much of an issue if we all did it at the same time and on the same date around the globe.