You can't compress something that is already compressed. Any further compression applied will increase size because of adding headers and hashes and the data will stay the same.
The issue is caused by a bug in the KB3057839 windows update. The bug has been reported to Microsoft and can be tracked at the following link: https://connect.microsoft.com/VisualStudio/feedback/details/1475291 Currently the only workaround is to revert the KB3057839 update on the production server.
Adding CSS styles for the table layout via the TableCssLayoutTemplates adds the style element inside the body, which is non W3C compliant content.