[ozim]

Contrived example does not serve the argument well, if someone is starting with "our users are complaining that our system is slow!", they could already do some legwork and check for themselves or check with users before dropping it directly on the engineer.

If someone goes to a surgeon he does not start with "I don't feel well, do something about it please", that what general practitioner is for.

I understand there are small companies where engineer is basically support as well, but for any bigger operation follow up question on "what part of system is slow" should be worked out on support level and provided with question to the engineer.