In the old nvidiastereodrivers convergence was is saved in the registry. You should be able to search it (HKEY_LOCAL_MACHINE\SOFTWARE\NVIDIA Corporation... something...) in the registry. You can export parts of the registry to import when reinstalling etc... Dunno if it works just as "easy" for winvista/7 though.
And i know: Even if possible it's not really a convenient way to do it.
it works, and it can be suprisingly easy, I can make an article but not that interested, lol
1. you make the nvidia stereo registry settings read only
2. launch the game, and try settings
3. everytime you press ctrl+F7 , convergence value is displayed onscreen, but not saved
so I suppose you can alter these by launching different .reg files, like you are using presets.
-Found this by accident!!!