What they are saying is that every view (button, checkbox, textfield, menu, etc) needs to be able to get "focus" by the user just pressing the left, right, up and down buttons (DPAD) while running your app.
If some views can only be selected by touching the screen, then thats not a good thing because Android TV devices usually don't have a touch-screen.
What this means is that you might need to trap the arrow keys in the Key_Press event and programmically move the focus to controls that are otherwise are not able to get focus using the arrow keys.