Back in the Dark Ages of Wall Street, when Dow 1,000 was heady stuff, a small company from Texas did something extraordinary. That was 40 years ago, and few could have predicted what would follow: the junk-finance revolution, the ’80s merger mania, the Michael Milken saga, on and on. Goodman, who worked with Milken at Drexel Burnham Lambert, is now one of the world’s leading practitioners of private credit, a fast-growing area where exuberance is running hot. Some look across the markets and see shades of 2007, right before the bottom fell out.