they wont force customers to update dash via a game, as games dont need the dash to run they just require the hardware, if they had to update the dash via a games disc then MS would have to enter agrements with various software houses, this would take a long time to iron out, as the software companies would fear a lose in revenue of there own games, as a lot of people would not buy the game if it updated without choice, and the software houses would have to carry out quality checks on the software, and this would make the games development more expensive for the software companie, so what if the companies dont agree then what can MS do, if that was the case they would add software to check for mods, bigger harddrives, flashed tsops, etc etc, they know about the font exploit and how it worked so they stopped it because they could, the reason they did not stop the game save exploit is because it would affect to many games and original legal use of game saves, so they didn't, the exploit was simple to solve because it did not relie on being signed now it does simple,
when my dashboard got messed up it give the error message but once a game was inserted it booted up straight into the game, the dashboard is there for extra features etc. So if MS wanted to autoupdate the xbox via games it would cause serious mayhem within the games developers houses and they would refuse and then maybe just make games for ps2 etc.