Let's not be coy about all this. Pulling the mixture fails the engine dead and the prop immediately windmills creating drag that will prevent a positive rate of climb. That is why the feathering propeller was designed in the first place. place. So the instructor has created an immediate serious emergency when there was nothing wrong with the engine in the first place.
I disagree, the situation is a very real and scary situation you could find yourself in the middle of, having some quality hands on training is valuable for actually dealing with the situation in real life.
Sure, its entails a greater level of risk than flying around on two engines, but when the instructor is both well trained and experienced, the risk can be greatly reduced.
A multi engine aircraft with EFATO, using the correct technique, is capable of climbing.
Its the application of the correct procedures, drills and technique that allows the aircraft to fly away from the ground, not whether the instructor retards the throttle or mixture.
Of course asymmetric training is a requirement; but I would have thought that common sense (good airmanship) would dictate caution when dicking around with practice engine failures near the ground, where the room for error is small. There will always be macho personalities among certain types of instructors who, in their misguided and even reckless enthusiasm, will risk the lives of their students in order to demonstrate realism. Wiser heads will have learned from the lessons of the past and realise there is a limit to realism, beyond which is sheer idiocy. Some may argue mixture cuts at low level fall into the latter category.
A37575, do you have a personal agenda ?, sounds to me like you dislike this instructor and are not willing to vary from this mindset.