I'd rather have that commit message than one that doesn't explain anything, but it's a bit verbose to my taste because I don't really care how he discovered the issue. I really just need to know what and why.

So let me link to my favorite author of consistently excellent commit messages, Jeff King on the git project itself:

https://github.com/git/git/commits?author=peff

To pick just one, here's a well explained single-line code change. It's subtle, so besides the excellent commit messages, he also adds a comment and a couple tests:

https://github.com/git/git/commit/1940a02dc1122d15706a7051ee...

Another example with an even greater ratio of explanation (10 paragraphs) to code (partial line change):

https://github.com/git/git/commit/8f32a5a6c050766bfa2827869e...

Oh these are great examples, thank you!