Usability of diffs, to do actual useful tasks, is an excellent research topic. But a very difficult area.

To add my subjective expt: I just compared myers vs histogram on my latest commit.

- myers presented a function I'd 90% gutted as the the same function, edited (the rest was moved in the file, so no LCS algo could find it), like word-diff often does. I thought this was clever.

- histogram presented it as one function deleted, and a completely new function added. This was cleaner.

But I'm not even sure which is more usable. Might even vary with the specific task, e.g. function evolution vs function readability. Difficult area!