Nate,
Thanks for dropping by. I don't own a MacBook Air. The article was written for any user who might want to use this method for installing the OS. The article was written and meant to be used for Mac users — e.g. frequent travelers — who may want a recovery installation that is more portable. I don't see how one could make a re-installation drive without the OS X image — either from one already stored on the HD or from physical media.