Oh dear.
For the SLF understandably confused: Yes, the "ex 747" guy could have been a little clearer.
He was trying to make the point about the aircraft dropping thousands of feet into imaginary air pockets. He came across as suggesting there will be no altitude change
at all. Of course this is never true, even in normal flight.
It only takes an altitude change equal to the diameter of the cabin for everything to hit the roof, if the change is sudden enough.
Even Fox news clears this up:
https://www.google.co.uk/url?sa=t&rc...S5bw8pxpDM-M3g
Then he (Vine) goes on:
"Is that why catering trolleys are so heavy?"
(So they won't float up in negative g)
Good grief.
Did he actually go to school?