Good-Day,
During my current game I captured an AI city that happened to have the same name as one of my other cities (Ares). When I tried to reinforce the city, my units ended up at the orginal city of Ares, instead of the destination city also named Ares. This was consistent and I found that I was left with a nearly empty city. When this city upgraded, I chose the "Random Guardian" upgrade in an effort to garrison the city. Subesequently, these "guardian units" also ended up in my original city of Ares. I was able to build companies of Dungeon Masters, which have managed to stay garrisoned in the city until the current turn. Since this city contained my only Earth Shard, I was loathe to leave it unguarded and hesistant to raze it (leaving me for several turns, at least, without Earth Mana).
On a related subject, I would like to see the ability to change the name of a city (ie Byzantium, Constantinople, Istanbul).