|notyetagm: Black To Play: 25 ... ?
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Maroczy's previous move was the terrible blunder 25 xd1??. Why is this a blunder? Putting this minor piece on the back rank <INTERFERES> with the communication of the White c1-queen and e1-rook. The White c1-queen is now undefended and lined up with the Black c5-queen through the White c2-pawn.
Therein lies the problem. The only White piece preventing Black from winning a whole queen with ... c5xc1 is the White c2-pawn, <BLOCKING> the c-file to cut-off the line of attack of the Black c5-queen at c2.
But if that White c2-pawn <BLOCKS> the c-file, who defends the d3-square against the knight fork 25 ... d3! ? Nobody. With 25 ... d3! Black wins a whole exchange with a simple knight fork due to the pin down the c-file.
<The defensive power of a pinned piece is merely illusory.> The White c2-pawn, <BLOCKING> the c-file to meet the threat of ... x, only -pretends- to <DEFEND> the d3-knight forking square.