That's right -- although in some areas, one might also have to deal with one level up -- which in Canada are the provinces. If a province wanted to change the name of a city, here in Ontario,Canada, the city has to comply. Things are always changing. In 1998, the province forced an amalgamation which created Metro Toronto out of the regional municipality of Metropolitan Toronto and its six constituent municipalities. As part of this, East York, Etobicoke, North York, Scarborough, York, and the City of Toronto (1834) were dissolved by an act of the Government of Ontario.
This happens with countries as well of
course (USSR), but it will happen much more frequently with
cities. That's another reason to go with a size definition with
a few other options for smaller states and perhaps some leeway
for historical reasons. The larger the city, the more stable the
name. I have no evidence of that, but it seems to make sense.
Marita