THE FLEECE ZIP-UP VEST, the capstone of a new corporate uniform, lurks in air-conditioned corporate cubicles across America. It covers the sweating backs of nervous interns ordering supersize coffees at Starbucks. It’s worn by silver-haired executives in the elevator, heading up to their corner suites. It appears in myriad shades of gray and blue, on men of all shapes and sizes who earn all kinds of salaries. It has become as ubiquitous as the take-out salad in humdrum workplaces, and is slowly supplanting the suit and tie as essential office wear.

Typically,...