A serial chief executive, the Republican presidential nominee is steeped in management theory and eschews gut instincts. He is not so much a micromanager as a microprocessor, wading deeply into the raw data usually left to junior aides. He entrusts advisers with responsibility, but keeps them on a short leash, monitoring them through a flurry of progress reports and review sessions. Mr. Romney is, colleagues said, “conflict-avoidant.” His decision-making process is unhurried and Socratic, his instinct to exhaustively debate and prod.

“He was not somebody who forced decisions to be made before they needed to,” said Geoffrey Rehnert, a longtime executive at Bain Capital.

In his approach, there are intriguing echoes of and departures from presidents past. His intensely hands-on style sets him apart from George W. Bush, the self-styled chairman of the board, and Ronald Reagan, who cared only for the big picture and left dirt-under-the-fingernails policy work to his staff. His tendency to immerse himself in the details recalls Lyndon B. Johnson, who closeted himself with Pentagon brass to personally choose targets for American bombers during the Vietnam War. His passion for mastering policy and deliberative decision-making evokes the man he wishes to replace, Barack Obama.