Airplane Toilet Safety

Garrison Keillor ponders the flush warnings in airplane bathrooms:

It is rather haunting, the notice above the Flush button in the toilet on the airliner, "Do Not Flush While Seated on Toilet." One imagines the engineers of the toilet running tests with flush dummies with big flat butts and the suction ripping the stuffing right out of them, and the engineers thinking, "Oh criminy, you mean we wasted three years on this sucker?" So lawyers were brought in to write the warning, which had to be short enough to be printed in large type so that geezers would see it, who are the ones most likely to flush while seated.