good mornings are probably the best accessory exercise you can do to improve your squat and dead. A FINE exercise for the hamstrings/glutes as well.. not to mention the brutal stretch that you won't get with other hamstring exercises.
As for the good morning squat, not sure what the use is but I'm sure the exercise isn't as dumb as some think.
I agree with the first part of this.
Good mornings will help you improve both your squats and deads (specially if like me you prefer do to it stiff legged).
The thing is I never have to much time during the week to do them, my lower back beeing under constant tension from both squats and SLDL.
A classic "do as I say don't do as I do".
But I really don't see the point of adding a squat to the movement.
It's like super-setting two compounds which is not the way I'd do it but I'm pretty sure that out there some people super-set compound movements and feel it's great.
I don't.