He was excoriated on tabloid front pages and by the mayor and governor. As thousands streamed across the Brooklyn Bridge on a frigid night during last week's transit strike, someone in a car yelled out his name, prefacing it with a curse. But now, a day after details of an agreement between the transit workers and the Metropolitan Transportation Authority were spelled out, Roger Toussaint, the union's president, seems to have emerged in a far better position than seemed likely just a few days ago. Mr. Toussaint, whose back appeared to be against the wall last week, can boast of...