Another anomaly and question about the ETA / time to target calculation

[Graf Geo]

I had recently wondered several times why the calculated time with LoRouter, profile walking/hiking, was often significantly longer, even though I had planned the routes on flat terrain. Sometimes 20-25% longer than the average speed set with the slider.

The only explanation for me is that the surface/trail condition is taken into account to a large extent if it is poor. In some cases, after checking in openStreetMap, I found that large parts of the route were labelled with surface = sand and smoothness = very bad, for example. This didn't always correspond to reality, but of course Locus can't help that. But where the paths were actually bad, you can still walk almost as fast as on normal paths, and by no means 20 or 25% slower. In my opinion, the condition of the path is weighted far too heavily for the calculation. In most cases, 10 % would be more realistic. But I realise that it is not easy to find a generally good factor.

But: in the bicycle profiles, the surface condition is apparently not or hardly taken into account at all! I have planned several routes for testing in different bike modes, the surface of which consists of sand and is labelled with smoothness = horrible. LoRouter calculates the same time as on a smooth tarmac road, i.e. at pretty much exactly the speed I set with the slider.

This is bad, especially as the influence of a poor surface on the time required for cycling is much greater than for walking or hiking. Cycling on sand or on tarmac makes a huge difference!

Take this route as an example: 2 km of flat sandy track (and really bad loose sand) through the pine forest:

https://link.locusmap.app/t/8g4c6s

In the LoRouter walking profile with the average speed set to 4 km/h (navigation commands ON), Locus calculates 39 minutes, which corresponds to 3.1 km/h. (However, we needed considerably less).

The same route is calculated in the LoRouter bicycle Touring profile (set to 14 km/h) with 8 minutes, which corresponds to 15 km/h. And that's on a terrible sandy track!

I have tried it on several routes in flat regions, and the bicycle profile apparently ignores a poor surface. Why?