Developer says GPT-6-Luna is a regression: switching back to 5.6-Luna fixed everything
ElectronicAd4565 · reddit · 2026-09-26
A developer who used to dismiss "the old model was better" complaints says GPT-6-Luna broke his workflow: after two days of struggling he suspected his own project or skills, but switching back to 5.6-Luna — with nothing else changed — immediately restored normal performance on hard tasks and natural-language back-and-forth. He calls the release "extremely disappointing."
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