I think the mixture has been used to simulate engine failure on every MECIR I have ever done! But then I have only ever flown with highly experienced ME Instructors. Can't say it has ever caused me any concern.
How do you realistically test whether someone verifies which engine has failed if that throttle is already pulled back?
EFATO
1) Identify - dead leg, dead engine
2) Verify - yes, I am right cause that throttle is already closed
3) Feather - same side as the already closed throttle
If anyone ever turned the fuel off on me - I would belt them with something and tell them, "don't f*cking touch that" - then land at the nearest aerodrome and tell them to get the f*ck out of my aeroplane!
Dr 