User finds ChatGPT Codex smarter and cheaper after removing custom instructions
doctor_dadbod · reddit · 2026-10-02
The author pays for a two-seat ChatGPT Business subscription to get zero data retention (ZDR), using GPT/Codex for repetitive clerical work via computer/browser use. His primary account carries custom instructions he reuses across AI apps — and that account performs terribly 1-1.5 days out of 5, burning usage rapidly, forcing frequent switches to a work-paid Claude.
He then used the second seat through the browser "raw" with no custom instructions, and it was dramatically better: far more usage-efficient, and he built two browser extensions (mixes of scoped and exploratory, iterative work with design/visual outputs). Comparing similar conversations, the unconfigured account clearly wins — suggesting generic custom instructions may degrade Codex performance and token efficiency.
Related event: Removing ChatGPT custom instructions may actually improve performance(2 posts)→
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