Route from Calw to Tübingen goes via Böblingen instead of Gärtringen

[leonardehrenfried]

A user has reported that the route from Calw to Tübingen correctly avoids Herrenberg due to the roadworks but takes a long detour via Böblingen: https://tinyurl.com/y9cq8usf

If you move the destination ever so slightly to the west, the desired route is chosen: https://tinyurl.com/yah3v49m

Causes

My hypothesis is that it's cause by the maxspeed tags on the route from Herrenberg to Tübingen.

Here is a tool to get an overlay of the speed tags: http://mijndev.openstreetmap.nl/~peewee32/maxspeed/Maxspeed.htm

The route from Herrenberg via Entringen and Unterjesingen has quite a few 70 kph speed limits.

The route via Holzgerlingen and the Schönbuch forrest has more 100 kph segments.

At the end of the day both are very unrealistic values and if you check the travel time it's not very realistic either. I think we need to tweak the algorithm for calculating the actual speed of a road.