Two other records are believed to have been achieved under a British format known as the "high score rule", in which a player's tournament result is determined only by the player's own scores, and not by the differentials between that player's scores and the opponents'. Play in this system "encourages elaborate setups often independently mined by the two players", and is significantly different from the standard game in which defensive considerations play a major role. While the "high score" rule has led to impressively high records, it is currently out of favor.