At the rate of climb of the NG over that altitude increase, I'm surprised the trapped wind pressure and possible escape plus the popping of the eustacion tubes didn't alert these 2?
I'm not advocating flying by the seat of the pants but occasionally this can indicate a systems malfunction or mis-setting..........
I refer the readers to my previous posting, a practice which I attribute to the dead science of "airmanship/common sense", written out of the plot in recent amendments of the "How to fly it" series of manuals!!!
