No. The instructions say fit holder, but the locating stop is hidden in the photo. Two tutors used different edges against it. We found that by comparing their setups.

Photograph the actual locating contacts. We had a lovely overhead view of a fixture that explained everything except what it sat against. The person who made the picture knew, so it never looked incomplete to them.

Who confirms the intended holder position before you photograph it again? I would not choose whichever tutor happened to get the nicer image.

The fixture designer confirmed it against the drawing. We have a new side view of the contacts and a marked orientation. Both tutors reproduced the intended position using the draft.

Can the wrong orientation still be fitted? A visible mark is useful, but the lesson should explain how an incorrect or incomplete seating is recognised rather than assuming the mark always gets followed.

How does the rejected cover look in that position?

Lin, the confirmed scratch is visible, but faint in the current light. Henry, the holder can still be reversed. The designer is reviewing the mounting arrangement; our draft requires the contact and orientation check meanwhile.

Good, two different jobs then. Fixing the holder instruction has not fixed the weak scratch image. Does the tutor's copy leave that lighting work visibly unfinished?

Yes. The holder revision now prevents the reversed fit, and both tutors repeated its seating check. Vision also compared the retained covers under two lighting arrangements and selected one for further presentation trials. The lesson identifies that as a trial, not a commissioned inspection method.

Include an incompletely seated example in those trials as well. Preventing reversal does not necessarily prevent the holder from stopping short of its intended contacts.

Added with the fixture designer. Thank you for that distinction. The next comparison includes correct seating and a recognisable incomplete seat, without changing the physical acceptance labels.