If I have a straightforward table of controls (two columns, label in first, control in second), and need to hide/display some of those controls depending on selections on the screen, the hidden controls leave whitespace behind, making the display of the data unbalanced. If you have two or three controls that are in consecutive rows and hide those together, you end up with a large chunk of white space chewing up real-estate on your screen. To get around this I have to stack tables, and show/hide the tables. This wouldn't be so bad, but it adds the padding between controls which I don't want to do. In addition, because you can't set column widths on tables, it's difficult to line up the columns of the stacked tables. It would be really nice if we could collapse rows entirely when the controls are hidden to make them truly disappear but keep the integrity of the layout.