I'm surprised Carlsen played a game with just 30 seconds on his clock; it's easy to lose in that situation since you simply don't have enough time to make more than about 30 moves. And by the way, the best player in the world at ridiculously short time controls ("bullet chess") like 1 minute for the game is Hikaru Nakamura, the top-rated American player, not Magnus Carlsen. Nakamura tends to play soundly in these time controls. Look at this video for a game where Nakamura plays against Grandmaster Max Dlugy (another bullet chess expert) with kibitzing by Grandmaster Ben Finegold: http://www.youtube.com/watch?v=Bzrap8Vtyq8