We have occasionally had the same experience with the routing on our RV 760 LMT. I have learned to look at the map view to check whether the routing is logical before driving.
Another issue we discovered recently is that the RV routing may not always be better for an RV than the auto routing. On a recent trip to a campground in PA, the GPS RV routing took us from the PA Turnpike exit over a number of miles of hilly, curvy, very narrow roads to get to the campground (after dark of course). The next day we found that the auto routing provided much less miles of narrow, curvy, hilly roads between the same two points. We have since used the auto routing option.