(Though I disagree, not sure why this comment was flagged? vouched for it)

If you have a big codebase, text diff is not faster to see what was done here and there, then a visual overview. I don't know about this project, but experimented with other tools of this kind and am building one myself. With text diff - you have to parse lots of text and you cannot see on one glance that, oh, these changes are in the rendering, this is DB - and here was done something with the server connection. If done right, I can immediately or very quickly see what was changed - and also decide if the agent (or human) did work in the right spots or gone off track. Now doing this right is not easy, but reading lot's of text is definitely slower then seeing, oh in this area there was a change.