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Wow! It actually makes sense!
(i.imgur.com)
Professionals have standards! Community for all proponents, defenders and junkies of the Metric (International) system, the ISO standards (including ISO 8601) and other ways of standardization or regulation!
What? I have never ever had a discussion in my life about tenths of celsius when discussing weather or thermostat. Nobody does that. The units are small enough to be used in majors.
Freezing is excellent point of reference when you think about what effects it has on our lives. When water freezes, roads get frozen. When water freezes, pipes might blow up. When temperature reaches 0 Fahrenheit, nothing happens. Everything is same as 1 fahrenheit, or -1 fahrenheit. Nothing has changed, it is completely arbitrary.