<p>I have been using latex since the mid-nineties for scientific publications without ever achieving any real mastery.  Out of frustration with the lack of suitable tools for automatic marking of changes (and envious of the nice graphical markup provided by -- at the time -- only Microsoft products), I wrote the latexdiff tool to achieve something similar for latex. Although it still has many flaws, it has been taken up by many users and at least for my papers, which admittedly not usually use heavy maths or unusual packages, works mostly 'out-of-the-box'.</p>

frederik