Why did the Nets acquire Paul Pierce and Kevin Garnett from Boston last offseason, mortgaging key future assets to do so? To help win a championship? To be on the floor in important moments in the playoffs, where their championship experience and leadership would prove invaluable to a team that previously had no players with real, legitimate postseason success? In the most important moments in the Brooklyn Nets’ season, the final minutes of the team’s Game 5 loss in Toronto, Pierce and