@Marinus-van-Deudekom
Interesting. in the Garmin, "Traffic" is a real-time service that alerts me to conditions up ahead. If an accident happened 10-minutes ago and is backing everything up, I'm alerted on the device. This service has nothing to do with how my route was originally imported into the Garmin and calculated.
Traffic related Recalculation can only happen if I allow it. in the Optimize Route navigation setting, I have the "On Request" set. In other words, I'm prompted (asked) if I want to route around the delay. Again, nothing happens unless I say yes to the reroute. If I do nothing, I'll sit with everyone else until the delay is resolved. But again (for emphasis), this has nothing to do with the original import/route calculation.
So, please explain the "Traffic info has a serious impact on the way Garmin treats the route".