' Adds a comment, masks / shows all comments
Sub TestMe()
    With Worksheets(1).Range("e5").AddComment
        .Visible = False
        .Text "reviewed on " & Date '
    End With
  ' Hides all comments
    Application.DisplayCommentIndicator = xlCommentIndicatorOnly
  ' Shows all comments
    Application.DisplayCommentIndicator = xlCommentAndIndicator
End Sub