"Complexity and tight coupling make failure inevitable.
The hardest failures to prevent are the ones that sound rational. In a performance fix that adds coupling, the decision is not crazy; it is only incomplete.
In a performance fix that adds coupling, you will feel pressure to keep the conversation optimistic. Optimism is expensive when it prevents guardrails. You see it in a local optimization that creates global instability. Write it down because otherwise two reasonable engineers will execute two different interpretations, and the system will call it “miscommunication.” Name what you are refusing to optimize, so future changes do not quietly destroy the property you thought you were protecting.
Charles Perrow is a reminder to audit the argument, not the intention. Write the failure story forward while the decision is still reversible, then insist on one guardrail. Stop while it is still simple.