Basically yes. Using your example, after 30yrs if i cant do the same job as someone younger it would be bad business for my employer not to replace me. People just need to be realistic, your employer owes you nothing , you are an employee. If they can hire two people to do the job for the price they pay you why not.Also i would think after 30yrs you should have a play "b" in place by now ! See that wasn't so bad