According to an anonymous developer who has "close ties" to the game, it wouldn't be difficult for EA and Maxis to allow users to play offline. With the server side having only minimal involvement in the game, particularly in single player mode.
In a conversation with gaming site Rock, Paper, Shotgun the developer said: "The servers are not handling any of the computation done to simulate the city you are playing. They are still acting as servers, doing some amount of computation to route messages of various types between both players and cities. As well, they're doing cloud storage of save games, interfacing with Origin, and all of that.
"But for the game itself? No, they’re not doing anything. I have no idea why they’re claiming otherwise. It’s possible that Bradshaw misunderstood or was misinformed, but otherwise I’m clueless."
This is somewhat contrary to what we've been told so far by EA and Maxis, which both claim significant processing is being done on EAs servers and that it would be difficult to change the game to work offline.
It seems too, according to a test done by Stephen Totilo for Kotaku, that the game can manage to run for as long as 19 minutes without a network connection. That would add some credibility to what the anonymous developer is saying, because it certainly suggests the server isn't doing all that much to keep things moving in single-player mode.
It's standard practice for games companies to get their titles as tightly woven into the cloud as possible. This, it has to be said, is more about preventing their losses through copyright infringement than convenience for the players, but it's becoming an inevitable part of gaming. And while the multiplayer aspect of SimCity is well thought-out, and of course needs to be online, there has to be some sort of compromise.
The server load issues are now starting to subside. EA has added more capacity, and disabled functionality to enable the game to use less server time and allow more people to connect. The big argument still remains for people who want to play while they're out and about, or if they just don't have a reliable internet connection. And given installs are validated against a unique serial number, we can't see how enabling offline would enable people downloading the game for free from torrent sites.
Fans of SimCity want an offline mode, and we can't help but agree with their arguments for having one and now it seems like it wouldn't be all that hard to implement. So EA, the ball is in your court.