Dual · In War, Crude Speed Wins

What the solver found: an exact audit of the classical manuals

13 moves

In War, Crude Speed Wins (兵贵拙速) — Elegant Pastime Manual (適情雅趣, 1570), no. 31 At move 3 the book plays Rf9+; Rxg10+ mates just as fast. A dual. The mainline is the book’s solution; a branch, where there is one, is what the solver found. Record from dpxq.com.