Consider George H. Ross, Mr. Trump’s real-estate lawyer for 30 years, who describes himself as the businessman’s “closest advisor.” In Mr. Ross’s 2006 how-to manual, “Trump-Style Negotiation: Powerful Strategies and Tactics for Mastering Every Deal,” he observes: “To my knowledge, Donald Trump has no negotiating weaknesses except maybe the fact that he doesn’t like to discuss minor details. He lacks the patience to work on unimportant paperwork, because he likes to focus on the big picture as a more productive usage of his time.”

Mr. Ross admires Mr. Trump, but he thinks this indifference is a fairly lethal weakness. Bad negotiators share an “inability to focus on the details,” he explains elsewhere in the book. “Trust me when I say the devil is in the details.” Then he adds: “You want to be the expert on the topic under negotiation” (his italics). Mr. Ross even advises readers who wind up across the negotiating table with “someone who thinks like Donald Trump” to offer to bore his subordinate with the minutiae. “This gives you complete control over the documentation process and who will make the day-to-day decisions. You have uncovered the real deal maker for your transaction—and it’s not the boss.”

If this was a critique, one particular boss didn’t seem to recognize it. “I like to work in broad strokes, deal with the big picture, but not the details,” Mr. Trump writes in the foreword. “For the details, I rely almost entirely on George.” Vladimir Putin, take note.