When, I was running survey crews in southern Nevada, we used to leave the office in the summer at around 0430. That way we got out and set up just before sunrise. Which gave us about 3 hours of working time before the heat waves got serious enough you couldn’t focus on a line rod.
I got a new boss one summer, when the guy I worked for got promoted. New boss decided that we couldn’t start until 0700. Then he wondered why we weren‘t getting much done. He and I argued about it for about a month. I finally took him out with us and let him look through the instrument. Couldn’t see a plumb bob at 100-feet. Finally decided that we could start whenever we pleased.
I can’t imagine that job without daylight savings time. And, most towns, and the counties have working hour, noise restrictions. 0700 before you can make 90-db at the property line. And with overnight lows in the 90s, it is hot by 0800 with DST. That extra hour of morning before the sun came up made a real difference.