I tried playing around with the UTF-8 mode settings but did not get a speed improvement.

After reading through the PEP it appears that on Windoes:

"To allow for better cross-platform binary portability and to adjust automatically to future changes in locale availability, these checks will be implemented at runtime on all platforms other than Windows, rather than attempting to determine which locales to try at compile time."

So if i'm understanding this correctly the locale coercion would not be controllable from Windows after Python is compiled?