I sort of agree but what I try to do is put more comments and documentation in the source code directly.
The problem is that commit messages are usually hidden only when there's a problem.
Comments are there for the life of the code.
The problem with comments though is that they could go stale and something could be refactored.
I try to put them directly on methods/functions more and not on specific lines of code.
If I have to document a line of code it probably is a sign that it should be a function/method itself as it's a bit too funky to just stand alone.
Commit messages are GREAT for tracking down when something is broken though.
Would be nice to have your IDE take your code comments and make commit messages for new methods and the documentation for that method/class.