Unfortunately his early success seems to have made him lose some focus.
Carlsen can't have lost focus all that much though, he has performed 2815+ in all his nine latest tournaments. No other active player has ever been close to such a performance sequence.
Accdg. to modern GM's today and computer analysis, Capablanca always plays perfect, flawless and never seen a single weakness on his games. On the contrary to Karpov and kasparov admitted that they'd made a lot of errors during their match.
Capablanca was a very strong player but if he always played perfect and flawless chess he wouldn't have lost any games, and as it is he didn't only lose the match against Alekhine but had rather "human" results against some other Masters, for example 2 wins, 2 losses and 8 draws against Spielmann. Some GM's are much more critical of Capa than I ever would be though, GM Gormally writes:
"But what about Capa? How would he compare strength-wise to the players of today? I think he would come off rather badly. The difference in terms of knowledge and understanding between the players of today and the players of the 1920s and 30s is enormous."
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