I honestly don’t know what delete_row actually does, I’ve never used it, haven’t had a reason to yet. According to the documentation it deletes the entire row and is not supposed to just clear the values from it. So if the repeater has 5 rows and you delete on of them then it should only have 4 rows, at least that’s what I get from reading this http://www.advancedcustomfields.com/resources/delete_row/
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