Tin.....
First to answer your question regarding getting power back with the mixture.... I can see no reason why it would not come back every time...barring something breaking.
However before you return the mixture to the position that restores the fuel flow you have that extra chore of reducing the throttle setting to prevent the engine from surging as fuel flow is restored.
We of course could wear out our fingers discussing our favourite methods of teaching, none of us are perfect and we alll have different ideas molded by our own personal experiences.
Me I go for the least stressful methods of performing any exercise and try and teach it in a manner that will fit more complex engines that can be damaged by sudden power loss.
Engine failures in twin engine aircraft ( one engine failing. ) will result in yaw being induced, I teach them recognize and control yaw and think at the same time.
Chuck