The Best Choice or a Positional Mistake?

Continuing with Fischer - Reshevsky, Match 1961 (Game 2), in the diagrammed position, White has sacrificed a Pawn for better development, the initiative, and pressure against Black's castled King. Reshevsky played 16...e6, and Fischer commented,

The best choice in a difficult position. Up to here we had both played briskly, but now Reshevsky began to consume time on the clock. After 16...Nd7 17.O-O-O Ne5 18.Qe2, Black's game is lifeless. White has 19.h3 and 19.Bd4 in the offing.

Kasparov disagreed.

1961 Match (game 2)
Reshevsky, Samuel

Fischer, Robert
(After 16.Qd1-d3)
[FEN "r1bq1rk1/pp2ppbp/n4n2/3P4/6p1/PNNQB3/1PP3BP/R3K2R b KQ - 0 16"]

The 13th World Champion wrote,

Played after a long think: Sammy was trying to find his way in an unfamiliar situation. In Fischer's opinion, [16...e6] is 'the best choice in a difficult position', but in my view it is a positional mistake: the opening of the center can only be to White's advantage.

After the slow 16...Nd7 17.h3! Ne5 18.Qe2 g3 19.Bf4 Ng6 20.Bxg3 or 16...Nc7 17.O-O-O Nce8 18.h3 g3 19.Ne2 Nd6 20.Nxg3 Bd7 21.Nd4!, Black also fails to solve all his problems.

Apparently the best way out was 16...Qd6! 17.O-O-O, and now not 17...Bd7 (the source game: Nei - Pitskaar, Tallinn 1951), after which Fischer was probably planning 18.h3!, but 17...Nh5 18.h3 Nf4, exchanging one of the powerful White Bishops.

where the last variation was taken from a game played in 1997. Disagreeing with Kasparov's chess sense is obviously a doubtful business, but White's 18.h3 doesn't look forced. Why not 16...Qd6 17.O-O-O Nh5 18.Ne4? If 18...Qg6, then 19.Rhf1, or 18...Qc7 19.d6 exd6 20.Rhf1, in both cases preventing the Knight from getting to f4. If 18...Bf5, then 19.Nxd6 Bxd3 20.Nxb7.

After 16...e6, the game continued 17.O-O-O Nxd5 18.h3 g3 19.Rhg1, reaching another position where the opinions of Fischer and Kasparov again diverge. I'll cover that in a future post.

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Later: Re 'another position where the opinions of Fischer and Kasparov again diverge [and] I'll cover that in a future post', I'm not sure what to say. Fischer gave Reshevsky's 19....Qd6 a '!', while Kasparov gave it '?!'. Kasparov, however, didn't show that Black had a better move, while the game continuation presented White with certain problems. Perhaps Kasparov's '?!' is a typo. Otherwise I don't understand it.