Too many holes not enough cheese?
The thread seems to be drifting away from the problem in discussing autoflight and tired flight engineers.
Being tired is fairly normal for many professions working long and difficult hours. You learn to live with it and recognise when you are vulnerable. Being fatigued is a different matter for discussion between pilot groups, management and authority. Too often we wave the tired / fatigue flag as soon as we make a mistake.
Standard procedures are your friend when you are tired and need to be adhered to even more vigorously. If the captain had ascertained that his aircraft really was safe to fly before scribbling his signature on the tech log and if the F/O had properly supported his captain by performing a proper pre-flight inspection then none of this would have happened.
Highly unprofessional.