An airliner passing a perfect 5 mile/3 degree FAF fully configured and on Vref is going to carry a substantial amount of thrust to stay at V ref.
Sure, but to reduce the total energy at a rate equivalent to a flight path angle of 4.5 degrees you need to reduce the thrust and/or increase drag,
OK465,
I'm saying that if you descend at an angle of 3.4 degrees while reducing speed from 180 to 137 kt your thrust minus drag is equal to that for a 4.5 degree angle at constant speed.