The issue is that when a journal is deleted, all of its actual content and user information is removed from view. (or, when purged, removed entirely.) But there's no mention in FAQ 16 of what happens to the comments you've posted elsewhere in other journals or communities.
Should something be added about that? That even if your journal is purged, comments you've left elsewhere remain in place? (For users concerned about "completely deleting all trace of my journal" and so on.)
I'm not sure it's important enough, so that's why I'm just generally tossing it up for discussion here.