Are there other examples for the RSV reading of τοσούτου as a story-telling generalisation or redactors choice to remove a specific detail from the narrative?
So far as I read them, neither BADG nor LSJ were written to address this point - whether it was a technique available to story tellers and editors to remove details that are not deemed relevant to the story.
An example from one of the papyri, 244/243BC ARSINOITE PPETR2,29B;WCHR334
κε[χει]ρογραφήκασι τὸν εἰθισμένον
[10]ὅρκον τοσούτου μεμισθῶσθαι.
P.Petr.: The Flinders Petrie Papyri. (n.d.). Perseus Digital Library.
Is the discourse-level usage marking the end of a section, ie. “that’s all” mentioned explicitly in any of the lexica either?
[There is a methodological flaw in slipping. Cutting up the text into the smallest intelligible context is going to lead to a understanding the text resembling a study of fruit that comes from a person studying fruit salad. The most obvious way that it manifests is in not noticing the vocabulary usage patterns within the dual speech-styles, and here now too when the discourse significance of words is not observed / recorded.]