2.1.1787 Part 4 Section 220.127.116.11, RowHidden (Comment's Row is Hidden)
a. The standard could imply that the RowHidden element may be used to hide a row.
Office uses RowHidden as an indicator of whether the row of the cell to which this comment points is hidden and cannot be used for hiding a row. The hidden attribute of the row element ("[ECMA-376] Part 4 §18.104.22.168; row") is used for hiding a row.