and this one?
They look identical, but the latter one is hiding a secret waiting to catch the person not being careful. In the second version, track changes are turned on, but the view is set to final.
Why does this matter? Because if you change the view to "Final: Show Markup", you see a lot more:
If you had emailed out this document to opposing counsel thinking that you were only sending the original example from above, imagine your surprise when they start asking you about whether the fox was brown or red and whether the dog is really lazy. They will know your thinking because you sent them your revisions.
The moral: if you are going to use track changes, and by all means you should, be certain to either accept or reject all changes and remove all comments before sending it outside your firm.