Clickbait headline. The mistake was a configuration issue in alerts that didn't matter at all that he spotted right away but intended to fix later.

Even the second mistake by the electrical contractor didn't result in any damages.

No meltdowns here. Just a funny coincidence.

I really hate the way The Register use terms like "techie" and "boffin". It always comes across to me as anti-intellectual.

This is just a click bait headline ...the article is rather silly and pointless.

When reading the article, you realise that the techie who went home without fixing his mistake was not the developer whose Celsius/Fahrenheit change created the false alarms, but the electrician who tripped all the breakers in the building and went home without telling anyone.

Classic https://en.m.wikipedia.org/wiki/Swiss_cheese_model

Another unit conversion issue.

It's research, just use international system units which are standard in science.