The official Japanese rules of Go are extremely complicated. It’s not possible to concisely explain them, without being imprecise about what would happen in a lot of unusual cases.
@flovo quotes at length from portions of the official rules, but even those words are really not enough to fully capture what’s going on with the Japanese rules, since there’s a lot of ambiguity and confusing situations that are only explained via numerous examples in a much longer official commentary attached to the rules. Even after working through all of the rules and the commentary, some questions and doubts will likely remain.
In practice, the vast majority of people (nearly everyone except for professional players and the referees that oversee professional tournaments) work with vastly simplified approximations of the Japanese rules. Most players don’t even realize how much complexity they’ve simplified away, since at some point, in order to learn a basic idea of the rules, a simplified version of the rules had to be presented to them, and a lot of the complicated situations often don’t ever come up.
Luckily, the situations that create the most complex issues and differences for the Japanese rules are also quite rare. Some are so rare, that you will likely never encounter them. In the vast majority of games, something weird won’t happen, and it won’t really matter if one uses Japanese, Chinese, New Zealand, AGA, or any other common rule set.
However, your question is very ambiguous, and seems to be concerned about situations where somethings may have been left unfinished, which can produces some of the weird cases that are tricky to deal with.
Resuming the game to settle disputes by “playing it out” is widely practiced, even though it is not exactly correct to do so (under the Japanese rules, but this is the correct procedure for other area-scoring rules), and would produce wildly different results in some cases. The only correct way to settle many potential disputes is to carefully work through the technical details of the Japanese rules, for which there are no easy shortcuts that provide correct results.
@flovo seems to suggest that I can give you a precise answer. However, honestly, I cannot tell you how to correctly resolve every single possible disputable situation with precise application of the official Japanese rules. Their full complexity is beyond my understanding, and there are surely many, many positions that will leave me stumped.
I may have given others the impression that I understand the Japanese rules, since I have been writing another thread that works through some of the complicated situations:
@VicktorVauhn, if you want to dive down the rabbit hole, you might find the above link interesting.
However, please keep in mind that what I have written is nowhere near an exhaustive exposition of the complexity of the Japanese rules, but rather it is:
- A work in progress with several other topics that I plan to write about.
- Even when I am done, what I have written will only really show the “tip of the iceberg”. There is far more that I don’t really understand and hence won’t be writing about.
I don’t understand the Japanese rules. I just know enough to realize how little I understand them.