I have a friend who lives in the US these days and I have dinner with him about once a year when he’s in the country. This time we had a discussion about the New Zealand constitution and how much of it is made up of convention that, technically, isn’t actually enforceable by the courts. These conventions include the Governor-General not actually having any power, even though the written parts of the constitution say the GG has the power to dissolve or summon Parliament and appoint or fire Ministers and other senior officials like judges.
Now obviously that convention is in fact a pretty powerful thing, not something that anyone would break on a whim or even at all, because there would probably be mutiny in the House and riots in the streets. But hypothetically you could. Which leads to a really fascinating “what if?” scenario where the Governor-General decides to up and institute a government of their choice (or the Sovereign’s choice even), a Cabinet of their choice, and just take over the country. I mean, they’d have to find enough MPs and Ministers willing to cooperate, but the fact that it’s technically possibly with no real LEGAL response is a pretty fascinating aspect of our constitution, IMO.