A Century of Chess: London 1922
Capablanca at his most machine-like, the feeling of playing against a computer that won’t make a mistake.
His closest call came in the game against Vidmar, a classic of sportsmanship. He had a completely won position at the adjournment. He and Vidmar talked about whether they would play on, but the the conversation was in French, which Capablanca did not understand well. Upon resumption, Vidmar appeared in the playing hall and Capablanca didn’t. With seconds left before Capablanca would have forfeited, Vidmar finally realized what was happening, dove across the playing hall and tipped his king just before Capablanca’s flag fell. It has been termed “the most beautiful move ever made.”
The next-closest call may have been in the last-round game against the Italian Davide Marotti. Capablanca once again disappeared from the paying hall, leaving only his raincoat. A spectator, noticing that Capablanca’s clock was ticking and had consumed 15 minutes, went to look for him and found him flirting with a woman at the bar. The spectator pointed out that it was Capablanca’s move, to which Capablanca said, “Is my raincoat there?" When the spectator confirmed that it was, he said, "Well, that should be enough for Marotti," continued flirting and eventually went back to the board and of course won easily.
He scored +11 against a world-class field and won by making the most of microscopic advantages.
The tournament was also a station in the unofficial vice-championship of the world, with Alekhine continuing to supplant Rubinstein as Capablanca’s most likely challenger. The feeling was that Rubinstein's powers were visibly slipping. "Formerly, Rubinstein never played so anxiously," Geza Maróczy wrote in the tournament book.
Vidmar had another of his unassumingly strong performances, taking third place.
Euwe’s growing pains continued, as he finished with a -4 score and his games included several bad blunders.
There are two really enduring legacies of the tournament in the chess world. One is the 'London Rules,' a set of agreements for future world championships agreed to by top masters (at Capablanca's instigation) on an off-day during the tournament. The rules themselves were reasonable, but the $10,000 called for for a challenge was prohibitive to just about everyone. The other legacy is the 'London System,' that quaint, somehow very English opening that got a new lease on life at this tournament. 
Sources: There's a published tournament book by Géza Maróczy. Edward Winter has one of his bravura blog posts on this tournament, full of interesting images and casting some doubt on the oft-repeated Vidmar-Capablanca story. Simaginfan elucidates the London Rules here. Chessbase has a write-up on the tournament here.
