Easier removal of grouping columns

The Grouping view shows a grid with the selected grouping columns and some calculated columns (by default "_count" for the number of rows in each group).
It is possible to select one or more grouping columns and undo the grouping with the "remove grouping column" button, but if the selected columns include "_count" the button does nothing (I assume because not all selected columns are grouping columns).

I think that in the interest of ease of use it would be better to ignore that some calculated columns are selected and just remove the selected grouping columns; the restriction is in a way logical, but not useful.