With the old interface, you were guaranteed that every column would fit the viewport width to 100%.
With the new one, if you add more columns, it forces you to scroll left and right to see everything.
Not only that, but there is a maximum number of columns allowed.
Why enforce a maximum number of columns if the screen is just going to force a horizontal scrollbar anyway? Seems rather arbitrary to me, the whole point of a maximum number of columns would be to stop the horizontal scrollbar from appearing.
