Rhetorical discussions may call an expression an apparent addition, but that does not mean it is pointless. A modifier can clarify the scene; coordination can add a new dimension; repetition may emphasize, differentiate, or correct an earlier assumption.
The claim that a basic assertion remains understandable without a word is not the same as the claim that the word has no semantic or rhetorical function. Connections between statements can depend upon wa, fa, and other linking constructions.
When an expression recurs, ask whether the audience or subject has shifted, whether a new restriction or consequence has appeared, and what emphasis results. These questions prevent repetition from being mistaken for mechanical duplication.