Remove Twenty Twelve themes responsiveness in Internet Explorer

by

  1. Create a child theme of TwentyTwelve.
  2. Copy the header.php to your child theme directory. Modify it to add conditional comments to load an “Internet Exlorer” only version of you stylesheet.

Use TwentyTwelve’s style.css as a starting point to create your IE only CSS file, or just override the responsive bits that you don’t like.