I don't know the 777 but in the 737/757/747 manual flying an approach with the A/T on worked well for me. It took a little while to get used to the effect on pitch, but I always held on to the throttles so I got advanced notice of the changes as the throttles moved before the actual thrust changed.
I was very easy and not confusing at all.
Very comforting in fact, knowing that the airplane was responding to the changes and maintaining the selected speed to a very close tolerance..
What was the benefit? It gave me very good speed control, especially in gusty conditions, and allowed me to use Vref+5 as the target speed vice Vref +5 +gusts. Especially on short runways it was a bonus.
Not of much use in calm conditions, so I did not use it all the time and some airlines I worked with banned it as a practice although I don't remember if Boeing did allow it.