Originally Posted by
rm -rf
Google's Bike map option will pick the most direct route that allows bikes, but often it's not the best way.
That isn't true unless they have changed their algorithms. I have had them take me pretty far out of the way to hit a bike trail (not what I wanted). As far as the "best way", there isn't any such thing. One rider may want the most direct route another may be willing to go well out of their way for any number of reasons. One may be traffic tolerant another not. One may want paved roads only another may like gravel. So there isn't way of choosing will always result in the best route for everyone. Personally I usually choose a pretty direct route when possible, don't mind some traffic, don't particularly favor bike trails, and prefer good surfaces unless on a MTB back country tour.
Looking at google bike directions and their car "avoid highways" directions is a good place to start, but some checking is needed. That checking can often be done using street view.