Is it always legal to replace the kanji iteration mark 々 by the kanji it represents? If not: When is it legal to replace "K々" by "KK" for some kanji K?
I am aware of three use cases of 々:
- reduplication (possibly involving rendaku), such as 人々 (ひとびと)
- certain names, such as 佐々木 (ささき)
- some compound nouns of the form [A B] [B C] (written exceptionally as AB々C), such as ほげほげ町々会 (where ほげ represents a name) and 結婚式々場
As I am a real beginner, I dare neither elaborate on any of these cases nor speculate about what common practice might be.
I would find information about any of the following interesting:
- what some authorities consider correct
- what majority usage is
- how deviations from majority usage might be perceived
- usage in poetry (where more creative license might be taken)