B was the only way to swap the view, and the game is meant to be flyable
without a controller - the arrows fly it when there is no pad. Somebody
without one had no way to zoom at all.
Tested ABOVE the pad test rather than beside the arrows, and that is the
distinction: which way the lander is flown is a question a controller
answers better, so the arrows stand aside for one. How much of the moon
is on the screen is not that kind of question, and a player with a pad
may still have a keyboard in front of them.
No edge to remember here either. The console delivers a key ONCE, which
is the whole difference between a key and a held button.
The check puts the z forty bytes into the keyboard file, because the
console hands over one key a frame: a z two hundred bytes in is a z two
hundred frames away, which is past the end of the capture and reads
exactly like a key that does nothing. It cost a wrong answer first time.