<i>"Having a clean history where each commit does one thing and only one thing saves you huge amounts of work when you are trying to find a bug in the code"</i><p>Especially when employing 'git bisect': <a href="http://www.kernel.org/pub/software/scm/git-core/docs/git-bisect.html" rel="nofollow">http://www.kernel.org/pub/software/scm/git-core/docs/git-bis...</a>