"Michael Nouak" wrote
I'm not saying you're wrong, however I am curious: You "could do
125nm easily" how? With the engines shut down? 'Cause that's
what a glide is to me. At idle you're still producing thrust,
even more so a flight idle.

Based on the chart numbers for an idle thrust descent,(about 1200#
total for all 4 engines) there wasn't much thrust being developed.
In the old days, our standard descent speed was probably 50-60 kts
above the speed for best L/D and we still flight planned for a
descent distance of 120 nm from FL370 at idle thrust.

Bob Moore