Re. Great Western Express, services run #1, 1C02, Class 43 HST power....Operating at 120 mph should give a closure speed of 2 miles per minute, or 200 kph=2 kpm. On the long 30+ mile run, distance counter does NOT appear to be counting down at the appropriate rate. I ignored acceleration rate, had train running at exactly 120mph, and noted closing speed, it was incorrect! Anyone else see similar discrepancy? Patch in the near future?
The distance that appears in the top left is calculated in a straight line from your position to the task (I think the term is 'as the crow flies'?). This could be why you saw the difference. The speedometer is correct, and so is the distance - but in a straight line and doesn't take into account the actual track distance.
This can be nicely seen on RSN. When approaching Hagen you have to go round a very long left turn sequence. The distance to Hagen hover at 4-5km for a long time while doing so, until you finally get closer to the station.