Quite a few horses have lately nourished the illusion that we might, collectively, actually know what we're doing. Sierra Leone (Gun Runner), for instance, is threatening to make sense of the second-highest price paid for an American yearling in 2022; while Newgate (Into Mischief) is steadily working off a $850,000 debt of his own, while similarly bringing closer the real payday at stud. But last weekend we were given yet another reminder of the genetic powder-keg lit by a mating strategy that can only have prompted a supercilious smile in...