My daily commute to school is about 20 miles, and my Nuvi always suggests the same route. This route always takes me through a particular intersection, which I'll call "Point A".

The other day, I drove the first part of the route without having the GPS guide me, waited until I was just past "Point A", and THEN told the GPS to route me the rest of the way to school. The strange thing is, the route it suggested from Point A to school was significantly different from the route it normally gives me when I have the GPS guide me for the entire trip, even though I was right where I would have been (exact same location, direction, and speed) if I had the GPS guide me for the entire trip.

I let the Traffic Monitoring subscription lapse, and I don't even have the TMC receiver installed, so I know the routing difference isn't because of TMC. This was on a Saturday around noon, and I'm usually driving to school around 7am on weekdays, so I'm wondering if the Nuvi makes some crude estimates about traffic flow based on time-of-day or day of the week, even without TMC.