Manual Flight should not compromise safety
Rick777 - when you refer above to turning off all of the automation am I correct to take that as autopilot, flight director, and autothrottles? Or are you also referring to selecting the lowest level of augmentation available (i.e., Direct Mode via the overhead PFS Disconnect switch on the B777)?
All - Disengaging the autopilot, flight director, and autothrottles should not result in comprimised safety. Without the autopilot altitude deviation during cruise will likely be greater and without the autothrottle speed control will not be as tight - those are given. The flight crew, however should be able to stay within expected ATC margins of assigned altitudes and speeds and should be able to adequately perform all phases of flight needed to safely arrive at their destination. Achieving this goal may require more experience flying manually at a wider range of flight conditions than is customary with today's routines.