I can’t imagine any other example where people voluntarily move for a black box approach.
Imagine taking a picture on autoshot mode and refusing to look at it. If the client doesn’t like it because it’s too bright, tweak the settings and shoot again, but never look at the output.
What is the logic here? Because if you can read code, I can’t imagine poking the result with black box testing being faster.
Are these people just handing off the review process to others? Are they unable to read code and hiding it? Why would you handicap yourself this way?
It is right often enough that your time is better spent testing the functionality than the code.
Sometimes it’s not right, and you need to re-instruct (often) or dive in (not very often).