Aero, you appear to overlook the effects of startle;
IMHO "Startle factor" is just another buzzword to excuse any cock-up by the pilot where quick thinking was required.
We all get startled occasionally; but hopefully for not long enough to make gross errors such as this event. In our profession there are very good pilots as well as those of far lesser skills; particularly when it comes to instrument flying. It is when the chips are down that those of us saddled with far less instrument flying skills, are more likely to react hastily and occasionally fatally.