If the controllerīs report (app LOM/ 6km distance) is done at a point of first appearing of LOM signal (ca 6,7 km) and if the distance 4 km is reported correctly, I calculated ground speed 388km/h. If report is done just above LOM, GS=340km/h. Both much more then 290km/h at the rest of fatal route.
Surely you can be right and it may be just pure coincidence that all distance reports lies almost exactly on the only streight line. Let us hope that soon the final report will give us the right answer. Maybe will not because this radar inacuracy factor looks irrelevant in sight of crash.