Bob - lucky you! I saw that book in the store recently and it looks very cool.
Guy - cute dog.
About the GPS, I just don't know. Over at GPSReview, this is a common complaint but not an issue I have seen much myself. I used a TomTom 920 for a year and was happy with the routing. Each time you created a new route, it would give you some options. It showed the whole route and if you didn't like it you could tap a button and it would continue to provide different routes as long as you kept tapping that button until you found one you liked. I thought that was a nice feature, but it may not be available on all models.
On the Nuvi (and TomTom also I believe) you can choose what you want to avoid. If you told it to avoid the highways then it wouldn't keep trying to take you back to one. But you need to dig down through the menu's to find this option, and many times you DO want it to route you on highways, so you'd need to keep changing this.
You also have the choice of shortest vs fastest routing. This may also affect the behavior - I'm sure TomTom also offers this. For me, I just go wherever I want and ignore the GPS if I disagree. Never bothers me, but I suspect that's because I don't have the voice prompts turned on. I can see how this would be annoying if a dumb "robot lady" keeps telling me to do something I don't want.