Carlsberg -
The speed in the MCP is set to 137kt, which includes 5 kt for the wind.
Vref is 132 kt, which is 1,3 stall speed
Stall speed is 101 kt.
Autothrottle will wake up a few knots before the stall, let's say 107 kt.
Auto throttle will not keep the speed at 137 kt in FLCH mode.
420,000 lbs, flaps 30, Vref 132. Bug 137 kts.
Stall speed is 106 kts(777 uses 1.25 Vso).
The concept of a hand on the throttles, or resting on the throttle quadrant behind the throttles, even with A/T's 'ON' and actually checking the N1's when the A/T's move is becoming a thing of the past.
But to do it on final, with speed decaying, and not catch it for so long? I don't care what automation confusion existed, from 500' until approx. 100', or less, the plane was below Vref, with throttles at idle, idle N1's, and no one did anything. That's Piloting 101, not automation 401.