I set my Rowlimit to 3, and added 3 items to my child list. My “show more items label” was “See more comments”. When I viewed the parent form, it showed my 3 comments from the child list, as expected. However, it ALSO showed the “See more comments” link. I would not have expected the “See more comments” link to appear unless I had 4 or more items on my child list.
Clicking on the “See more comments” link did not, of course, show any additional child items, since all child items were already being displayed. That could be confusing to users.