Quoting safetypee:
Are there any interesting vibrations, system selections, or characteristics which could contribute to such a theory during an approach in a 777?
Taking the AAIB reports published into consideration, (perhaps the investigation has progressed beyond what has been published sofar) if no evidence of an anomaly has been found:
Approaching the issue from another angle, i would go for a combination of system selections (including interaction or possible interference with other systems) and characteristics.
A question that comes to mind would then be: which (sub) system components could (due to a yet undefined fault) migrate from commanded position without generating a fault indication to the flight crew but result in reduced fuel flow and cause engine rollback?
A question related to the one above is, why was the APU door open during approach if there was no mention in the AAIB reports of an electrical power failure? Isn't the APU normally an after landing checklist item?
Green-dot