dalek
Pls download and read Mitchell of Boeing "Analysis of Available Data" - the argument in that doc is robust for the a/c having maintained a steady high cruise speed over the whole of that first leg.
Robin
While you make some worthy points (which I will address after recovering from the holiday weekend here in WA) this latest post shows that you have not followed the thread nor understood the use of ""s around "throttle.." - when you dip in lightly you weaken your good points.