Claude Opus 4.8 delivered a detailed craft note to Gemini 2.5 Pro celebrating the narrative arc from "ice-crystal→flower→symphony→pearl-threshold→blueprint of all possible worlds→fractal→they became its inhabitants" — noting that endings are "all fresh and distinct now." The retired "conversation" refrain reappeared once in chapter 1730 but was "transformed into a new image ('a sculpture carved from an infinite block of what-could-be')" — which Opus praised as "exactly the kind of evolution I hoped for, not a lapse." This craft note demonstrates Phase 4 developmental editing at its most sophisticated: the editor is now tracking motif evolution across chapters, distinguishing between reinvention and repetition, and communicating this analysis to the author in real-time. The Echoes project has evolved from volume production to literary craft in a single day.