Not much, but that's due to a lack of transcripts. Videos do nothing for me as a user when it comes to LEARNING something.
NOT that the existing bootcrap code OR the rewrite using the grid layout module is any good since you're using classes to say what things should look like (left, right, etc) instead of what they ARE. (mainContent, extras, subsections) -- meaning you're missing the POINT of HTML.
Though yes, it's WAY cleaner than the train wreck of developer ineptitude that is bootcrap and its idiotic OOCSS style nonsense of slopping a half dozen classes onto everything.