Quote from: Ulrich Kiermayr on October 15, 2016, 20:29:07@Ulrich Kiermayr - I recall the ETA calculation did something like what you propose a long time ago. At the time I made suggestion for opposite of what you now propose to return to i.e. "considering the current average speed" - help topic http://help.locusmap.eu/topic/why-was-time-to-target-so-wrong. No algorithm, unless it takes into account topography and history of your speeds in similar circumstance is going to be accurate, when there are range of gradients along the route, but in your example when cycling faster in second half, even after a few minutes of downhill your "current average speed" will of course quickly rise, and as a consequence the estimated ETA will indeed become more and more accurate? Didn't you observe that? Say you select a profile where the nominal speed is 18km/h, and on your route you cycle uphill all day, how is the profile speed any use to ETA calculation?
A remark on that: during our vacation (cycling) the ETA often was not really usable. Reason: the topography of the route has a huge influence on the speed you are able to ride. Consider a tour where you go uphill the first half and downhill on the second. Just considering the current average speed, would result in unusable results,because it would estimate going up the whole tour. But this is wrong, since the second half will be faster because it is downhill.
I think the ETA algorithm (for cycling and probably also for hiking) should work somewhat like the algorithm to estimate the time for a track. The current avg speed could\should be used to set the parameters for that estimate (like piking the best profile in the trip time estimate).