The upset is generally set up by one pilot while the other has his eyes closed. Great training!
Why close your eyes? In real life UA your eyes wouldn't be closed unless you were asleep. Both pilots would have their eyes wide open if they got themselves into a UA. I have seen some simulator instructors tell the pilot to look down at their knees and close their eyes while the instructor stuffs around tipping the simulator like a drunken sailor, deliberately missing trimming and even pulling back one engine. Quite nonsensical and impractical. Great training? WTF??
The closing of eyes was done in a Cessna 172 where a instrument flying hood is worn and in theory prevents the student from peeking out from the side of the hood to cheat and see the horizon. The simulator instructor can simply select IMC on his instructor panel so there is no chance of cheating.