say your driving down the motorway or a country road
is wifi useful in this scenario? no
Someone has already pointed out the error of needing to be connected to WiFi, but I would just like to add, I think I spend probably 90% of my life in reach of a WiFi signal of some sort. Of course, this is different person to person, I live in London but someone that lives in the countryside will be much less.
Also, people really don't change internet all that often, or move house... Pick 10 people in your street, probably only 1 of them has been there/changed internet providers in less than a year.
I'm also fairly sure the phone picks one way of locating. If GPS is off, it will default to WiFi. If that's off, it will drop to cell towers. Why in this order? Because that's the order of accuracy.
I think A-GPS means it uses data/rough position to help understand what satellites it should be able to see in the area it's in, rather than actually using the cell towers to give a position. I could be wrong, but I think it's backed up by this -
http://en.wikipedia.org/wiki/Assisted_GPS
Anyway, I'm not even too sure what we're arguing for now. Someone said you can't GPS lock in doors, you can.