Check Airman
Apologies for diverting this into another 'Boeing moving throttles vs. Airbus non-moving throttles debate' - that wasn't my intent. Rather I was trying to point out that I believe the differences training the Asiana PF received was inadequate - something I didn't see in the final report... The Boeing and Airbus design philosophies are considerably different - not saying one is better - but they are very different. That needs to be thoroughly accounted for in the training when switching between.
To understand the Boeing design philosophy for the autothrottle systems, you need to go back in time a bit. The original A/T installed on the 747 (FFRATS - Full Flight Regime Auto Throttle System) was an analog device and quite crude. It was simply intended to relieve crew work load on long haul flights, not to completely take over the task. Move on to the 757/767 A/T - which was digital and far more sophisticated than FFRATS, but had numerous potential failure modes (slipping lever clutches being a common one due to down-stream cable loads), and it was a single servo so could not control the levers independently. The software was only developed to DAL C (essential) - not flight critical - which was consistent with the rest of the system design. When we went to FADEC on the 767 and 747-400, the basic system didn't change that much from the original - getting rid of the throttle cables helped a lot (simple friction devices where added to the thrust levers to give 'feel' and prevent uncommanded movement since the force to move the thrust lever resolvers was minimal), and a 'trimmer' function was added to the A/T software that sent small adjustments to the commanded EPR/N1 of each engine to align EPR/N1 across the wing (to account for pilot induced throttle stagger or small rigging errors). But it was still single thread, with a single servo drive, and the s/w was DAL C. In short it was still viewed as an 'aid' and the pilot was still expected to monitor what it was doing.
The 777 got a completely new A/T relative to what was used in the
747-400/757/767 - dual servo so independent control of both engines, s/w was DAL B, but it still wasn't certified as a 'flight critical' function. On the engine side, we always had to assume 'worst case' - that the A/T could be lying and so we still needed provisions to disable it and ignore all inputs. We complained mightily that the A/T should be considered flight critical - that the pilots were starting to treat that way, but got nowhere.
My understanding - based on conversations with my cohorts who worked on the 787 - is that they finally designed the 787 autothrottle as a flight critical system. But I don't know details.