Thank you. After thinking about it overnight, I realized I asked a wrong question. Your answer still helps greatly and get me more than half way to satiate my curiosity.
Tolerance grade and example objects that require different grade/minimum pi accuracy is what I was looking for.

TIL there is a closer approximation than 22/7

Thank you, I already skimmed through that article before posting. Maybe I failed to put my question into words properly.

I want examples similar to pool/fence circumference in the article. Along the line of “We’re building x, and this is the worst rounding we can go, one fewer digit and it will be off by y”

I would not place my hope on kadokawa doing anything like that. I don’t think they even care about anime industry aside from make money part of it.

Great explanation, thank you.

Have not read the novel. I was confused the whole time watching S01.
Our man told bullshit story to his first recruit and now those bullshits are actually true??? Is it mentioned in the novel if the cult exist before or the bullshit itself created the cult? Or it will be reveal later?

By ‘repeat’ you mean continue from last save, right?
Right?