Click on the image on the right to see the full size.
The Alt-N keybinding is bound to two UI controls.
But since the “Next” button is later in the tab order, pressing Alt-N will switch to “Perform a new installation” and deselect the “Add feature to …”
Very handy indeed when you don’t want a new installation, but just quickly want to go to the next step in the wizard.
#fail
–jeroen