Beagle:
B777's Thrustlevers move! Thank god for that.
As the PF's hand will be on the throttles, he/she will know if the autothrottle is powering back without looking at the instruments.
Muscle memory will give him/her ample warning. After that it is just a matter of stopping the levers coming back to idle and as thrust is allways relevant to powerlever angle it will stop decaying. If you need more thrust just push them back up. No big deal.