Building on existing work in proxying interaction with proof assistants, we have previously developed a proof movie. We have now considered the problem of how to augment this movie data structure to support commentary on formal proof development. In this setting, we have studied extracting commentary from an online text by Pierce et al. [Pierce, B. C., C. Casinghino and M. Greenberg, Software foundations, Course notes, online at http://www.cis.upenn.edu/~bcpierce/sf/ (2010).].