Another is that they didn't have to learn how to use git commands. The downside is innumerable regressions as emailed commits overwrote previous code without a merge/diff/conflict process.

Git’s diff engine has a new heuristic for clarity in version 2.9. Diffs primarily show changes, additions, and deletions, King explained.

We agree that it shouldn’t be hard to roll visual diff functionality into open source software packages used for hardware design, and to integrate that into version control systems.