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My workaround was to turn off one monitor, startup the game and switch to windowed mode. I saved this setting and quit. Then I turned my second monitor back on and I play in a window. The game now starts up just fine in a window. The turn off the monitor dance is only required once.

If it matters, I'm running similar graphics hardware with the same drivers. I'm pretty sure nvidia lies a bit with twinview vs xinerama. I wouldn't be shocked if the screen size was being detected incorrectly by the game.