Somewhere it is mentioned that the apprentice worked for 30 minutes with the boss and then spent the rest of the day making up the ten receptacle covers.
They way the mind of the employee works that he has been given one task to do and must stretch it out to fill the remaining 7 1/2 hours of the day. It does not look beseeching to be caught doing nothing! Therefore, the time required for each assembly would be 45 minutes.
This would include measuring each stripped wire with dial calipers; stripping the wire v e r y s l o w ly so as not to raise any unwelcome electrostatic forces; filing the ends of each cut wire [assuming solid] to eliminate those crude, non-orthogonal cut marks; torqueing each screw with a torque screwdriver; grinding and honing the ends of the yoke where the eyelets were severed; and, of course, wrapping the whole thing with black phase tape to protect our friends -- the painters and drywallers. [However, in this case, leaving one bronze screw and one cadium screw extended is actually a time saving and wire nut saving move. This fella is thinking ahead!]
Or maybe, you might have said, "When you get finished with that, then you can go out and help dig that trench."
~Peter