Hm. I was indeed aware that WYSIWYG starts to disintegrate as soon as you share a document with another user <g>, but I'm sorry to have confirmation that Track Changes settings are also profile-dependent. Character-styles it is, then … and a quick check to find out whether these travel better. My hope and suspicion is that they might, as long as I'm not using Normal.dot for the base template.
For completeness, I'll report back.