[mannykannot]

This is an ideal (if not utopian) vision of software review (though please let's handle style checking automatically already!) It implicitly requires, however, such a thorough examination of the code that diffs would seem to be an irrelevant distraction.

In practice, however, starting from the changes in a system that was previously working well enough is a very effective way of focusing limited human attention on where the problems are likely to be, optimizing for error detection with limited resources over the broader knowledge-dissemination goals espoused in this approach. If we are going to use diffs, then this brings us back around to the topic if the article.

Personally, I find having any form of diff embedded in what I am trying to understand just makes it harder to follow, so I move the diffs onto a secondary screen and use it as a guide and reference to what has been changed. The author of the article seems to want the same, but the mock-up is somewhat misleading, as it only has substitutions and additions. Where something is removed or refactored to another place, the two views will no longer line up as depicted here.