The official line / admission from the World's Worst is much as in Rubberj's last para. Plus the fact that the thing just doesn't balance in turns.
They've also carried out an extensive survey (i.e Spent millions)which revealed that another major cause of "queasiness" is that, while the cabin air on, say, a 747 whistles in at face level from the outboard side, in the Cripple-7 it's circulated the other way, sluggishly, and effectively sucked upwards by heat from the central o/head lockers. Hence, no sense of "breeze" when standing in the aisles. Hence the staggering Cabin Crew. Apparently.
Then there's the Press.. Never mind auto-pilot.. What price auto-suggestion..?