I understand this is (probably) flagrantly missing the point of the article, but...
If someone did that illegal-card-during-concession thing in a game with 3+ players, would it be "trying to gain an advantage" and thus cheating if the game wasn't over yet, or are "gain an advantage" and "give someone an advantage" considered distinct?
Interesting consideration. If you cheated to improve someone else's situation and left the game, that's probably an infraction (inappropriate game actions) but probably not cheating (because you're just fucking with people, not trying to like, claim tournament winnings). Necessarily.