ToggleSmart works as expected in the first example but is always ignored in the second example when the sort column is specified with a plus prefix in order to add it if it's not already present.
Set SORTBY=modified SORTREVERSE=ToggleSmartClearly, ToggleSmart is logically redundant when a new column is added, but if the column already exists I would expect its sort order to be reversed, as happens with the first example.
Set SORTBY=+modified SORTREVERSE=ToggleSmartRegards, AB