User blog comment:DaNASCAT/Technical Update: March 20, 2012/@comment-3441771-20120326063434/@comment-824313-20120327225332

Although it's a few more clicks than you want, on comments with histories you can click the "history" link that appears in the corner on hover, then use the edit button to get to the source.

I also think a view source button would be a nice feature for comments.