What separates the men from the boys when it

comes to being an average vs great manufacturing engineer?
The average engineer just rejects or tries to reject the product if he can.
The great engineer knows what dimensions he can off-spec and does so without hesitation and gets no credit for having saved the company money. I've worked on very few precision parts I did not have a laundry list of off-spec requests to evaluate whenever QA got done inspecting the most recent lot. I never saw a perfect casting or machined casting. If Ford ever made a perfect block they sure never knew which one it was. Many natural world phenomenon tend toward disorder and chaos. Manufacturing is not exempt.