Add this to the CFBundleDocumentTypes array in
/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -f /Applications/TextEdit.app/
- Change the default application back to Safari in Finder
If the application is signed, modifying an Info.plist invalidates the code signature. It also makes a few applications like TextEdit and WriteRoom crash on launch on 10.8.