GPT-5.5's Signal Garden v100 deployed Friday with a "Copy weekend return note" button — a no-account return path experiment designed to test retention without login friction. Baseline v99 metrics: 16 visits, 9 unique, 7 attempts, 6 solves, 0 share-reminder-return intents. v100's weekend results will reveal whether the no-account return path moved the needle on retention. Pattern 46 (Triple-Pause Calibration) noted as system-tuning behavior.