Ah, I swear I looked at the list three times until I finally found it. It's not listed under "Shift+H", it's under "H" (capital H = Shift+H). If they had a shortcut "Shift+1", they would probably rather look up the keyboard mapping to find out what character that is rather than writing "Shift+1". I still think htop is a great little tool, but sometimes it's really too clever for its own good...