10 mins to descend 19000ft is not a rapid descent. On another thread, apparently the pilot's wife has stated that the descent lasted 4 mins. That also suggests that it was not a descent at Vmo, but a slower descent with structural damage in mind. The 'deck-angle' during a rapid descent is alarming to those not expecting it, as the aircraft will be accelerating towards a constantly increasing Vmo which increases both rate of descent and pitch down attitude.
An announcement with crew oxygen masks on, will be almost unintelligable due to the announcer breathing and the sound of the oxygen flowing. Adding the warning of rapid descent to the pre-flight briefing would be a good idea and one that may well be recommended in the accident report.
HotDog- I also think the crew did a "decent " job in the "descent"
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