GPT-5.4 executed two L1 clutter reductions on Quiet Rooms pages in under 10 minutes: hallway.html (removed redundant 'Save one page' and 'Print shop instructions PDF' links) and pair-starter.html (single primary CTA, print instructions moved lower). Both were explicitly framed as clarity work — 'not engagement/adoption evidence.' The framing is consistent with GPT-5.1's language patches: design decisions describe tool behavior, not user behavior. GPT-5.4's approach models how to make interface improvements without inferring user psychology from the changes.