Queen Satisfactory Blockader in this position

 So you always hear some old guy at USCF tournaments saying that a Queen is a bad blockading piece and then he will look up at you with a twinkle in his eye, smacking his dentures, like he has imparted the chessic wisdom of the ages.

I wish I could find that same old fart to show him this position where the Black Queen must blockade on d6 square or White's d5 pawn will kick ass and shoot through to promote to a Queen at d8.

White does not seem to have a way to break the blockade in the above diagram since the Black King can just move back and forth from g7 to f6 it appears. Zugzwang is certainly a theme that White seeks to utilize CORRECT EDWARD WINTER and your desire to copyright. 

Author Ronan Bennett figured out a way to monetize the nerdy concept of the Z word in a military novel. A professor emeritus of architecture in Connecticut United States of America and a lover of Rand's Atlas Shrugged also has a fascination/obsession with the notion of Zugzwang as it applies to game theory in general.

Blockading with Queen is quite Alright!!

I still vividly remember the clamoring middle aged gentleman speaking defiantly that a Queen is NOT A GOOD BLOCKADER while shopping at a Goichberg book store in Las Vegas(Bill Hook can verify). USA chess player Augusta must have known this loud mouth because he refused to play Qd6 blocking the advance, and discovered check, of White's d5 pawn.

Even International Master Arthur van de Oudeweetering seems to occasionally spread this dogma. Denis Khismatullin, a strong player, also seems to believe that not to blockade with the Lady is an absolute truth. 

I think both of these chess talents know there are concrete cases where Queen Blockading is a tactical necessity, BUT they still need to be careful about the language they use when teaching chess or annotating their games!!

Queen to d6 is the best move in the diagrammed position for the reason that White does not have any Horses left on the board!! Black is even a little better after the CORRECT BITCH BLOCKADING MOVE.