A little while ago, I asked this question about the Japanese point of view: How do you identify the point of view in Japanese (for novels)? The answer seemed to be that you need to watch for the pronouns, when there is some. I realised that there's more to it than just identifying if it's first or third person. Take this example from 浦島太郎 (Urashima Tarou), a known Japanese fairytale:
So far everything seems fine, this is the beginning of the story and an English speaker would think it translates to something like: "A long time ago, there was a very kind fisher. His name (was) Tarou Urashima. One day, around 6 kids gathered and bullied a turtle on the beach." The issue arises when later, this sentence is used:
This is very striking for an English speaker: "Tarou heard a voice calling him: "Tarou, Tarou". Next to the boat, a turtle is swimming." At first, I thought it was first person being suddenly used. But I kept the perspective of @aguijonazo in mind (from the other question): "Generally, I wouldn’t say it’s common to switch perspectives in one novel. I would think a work that freely switches between first-person and third-person modes would be considered a poor piece of writing." So then, if this isn't first person, this means that the third person narrator went from speaking of something in the past to being in the scene with 太郎さん. The narrator literally jumped in time.
These are my questions (from a Japanese perspective, not subjectively): Can the narrator jump in time whenever he wants in Japanese? Is this considered a poor piece of writing or very natural? An english speaker would expect 泳いでいました, would this also feel natural to use?