I think this is a flaw in your proof since to block a win the chess player can land a piece on a square above the winning square as well. If the C4 player plays solely in the A column the B column knight can go C3, B5, A7 to block on the third move.
I think this is a flaw in your proof since to block a win the chess player can land a piece on a square above the winning square as well. If the C4 player plays solely in the A column the B column knight can go C3, B5, A7 to block on the third move.
