I think Google did guess his home in example 3. It looks like Google Now tries to build a model of where your home is based on your GPS locations during sleeping hours.
The reason I think this is the case is that it kept on updating my "home" while I took a road trip across the East Coast. So when I moved from NYC to D.C. everyday it would tell me the commute to NYC (Home) because I had spent a few days there and Google thought I was based there.
The reason I think this is the case is that it kept on updating my "home" while I took a road trip across the East Coast. So when I moved from NYC to D.C. everyday it would tell me the commute to NYC (Home) because I had spent a few days there and Google thought I was based there.