nullmove

I can't imagine Anand ever playing Rb4 in any other situation except this one. Earlier on the move b5 was truly spectacular and gave Black the edge, I think this is the first time Anand gained such a dynamic initiative over Carlsen in this whole match (barring the game he won). Also Carlsen was short on time, I mean so was Anand himself but with one game left this was a now or never kind of moment. On the whole I feel that Rb4 was more of a hopeful and deliberate gamble (as in he knew what he was getting into) than an actual nervous breakdown.

This is only applicable for blindfolded simuls where one needs to remember all board configurations. If the GM (or the one providing simul) can see the board then he wouldn't need to track differences, he can simply play according to each board. Only in blindfold does he need to remember each configuration with perfect clarity so tiny differences can get very confusing.

Anyway, this reminds me of an anecdote I read long ago in a Tim Krabbe piece:

"A grandmaster once played a 10-board blind simul somewhere. Knowing the ropes of blind simuls, he varied his games right from the start, maybe opening two with 1.e4, two with 1.d4, one with 1.b3, and so on. To his suprise, all of his opponents played 1...b6. On the second move, five of them played 2...Bb7, and the other five 2...Ba6. On the third, three of the five players who had played 2...Bb7 now played 3...Bc8 and the other two played 3...Ba6, while three of the five who had played 2...Ba6 now played 3...Bb7, and the other two 3...Bc8. On move 4, the grandmaster saw bishops everywhere. After move 5, he excused himself and went to the toilet where he was happy to find a window big enough to let him through."