It seems that there is an erroneous assumption that above MSA there is (in my company) an SOP to apply full power and climb in reaction to a GPWS. There is not.
One of the reasons that passing MSA is acknowledged by both pilots is to reinforce the awareness of the company SOP regarding GPWS warnings, which is different depending on whether one is above or below MSA.
I am calling it a day on this one.
I can say that my company's GPWS SOPs are intrinsically safe.
I can also say that other SOPs that have been mentioned here will be safe most of the time.