On the other other hand, two pilots issuing opposite control inputs generally has a bit more impact than an empty printer tray. Boeing's relatively low-tech solution of making the two controls physically interlinked seems like a common-sense solution to a potentially immense issue.

But obviously the training did not suffice in the Air France case, because those were experienced Airbus pilots and they did not detect and resolve the contrary inputs.

Something easy to ignore when you're freaking out over a plane going straight into the ocean.