I wonder if the throttle move. In almost all aircraft, excepting the A3[2|3|4|8]0 family, throttles move when in any automatic mode. If the autoflight system decides to go to full throttle, they'll slide all the way forward. This was definitely true on the B7[5|6]7 series, but I'm not certain about the B777.
There were a rash of concerns (though no incidents that I recall) because pilots often leave a hand on the throttle to have a sense of what the aircraft is doing. A sudden movement could mean a change in flight mode or a level off, or a stall.
By contrast Airbus's non-moving throttles are just shiny switches. They have detente settings for each mode. They could just as easily be a set of toggle switches.
There were a rash of concerns (though no incidents that I recall) because pilots often leave a hand on the throttle to have a sense of what the aircraft is doing. A sudden movement could mean a change in flight mode or a level off, or a stall.
By contrast Airbus's non-moving throttles are just shiny switches. They have detente settings for each mode. They could just as easily be a set of toggle switches.