Huh? The facilities guy at the local nationally distributed yogurt based product company just swaps out impellers when told by the machine as it identifies ther

Huh? The facilities guy at the local nationally distributed yogurt based product company just swaps out impellers when told by the machine as it identifies there is an issue. He has less skill than your typical HVAC guy, and zero interests in the nuance and zero input about 'best yogurt cavitating' practices. The aircraft part is measured by Faro or some other tool. The person wielding the Faro just follows the QA instructions and marks if things are red/green. Another FARO type product measures the fixtures/etc for compliance. If they don't match, a fixtures consultant is brought in to make them match. Other than those that happened to do the initial setup/machine/fixture construction, the people in the actual plant don't really have much non-fungible skills in your example, and they definitely don't have power/permission to go tweaking things using their personal non-fungible skills.