I know this is probably not up for debate, as my guess is that currently codemax dictates how it works.
Yet I have to ask as this is how it is handled in most other programming languages on windows... and I like it better that way.

When I edit code in Visual Studio it stays in OEM until the Studio decides it cannot save it unless it is saved in unicode.

IOW. I do NOT get a BOM in each source file that I touch unless I add a character that requires it to be changed.

See this is what happens when I try to type in Thai in my source in VS.

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If the Studio doesn't change EACH and EVERY file over to unicode as soon as I type a character then it would mean a lot more peace in our source control world.

FWIW, delphi does something similar too.

edit: and now you say "so don't type in your source"...