When the Washington Capitals take the ice Thursday night in Philadelphia, there will only be one player on their roster who remembers what it was like 10 years ago, when the team had completed a blockbuster trade for Jaromir Jagr. There is only one player who remembers how the experiment failed and management jettisoned Jagr after 21 / 2 seasons during which the former NHL scoring leader never lived up to the hype with which he arrived. How correcting the error marked the beginning of the Capitals' decision to tear up their roster in 2004 and rebuild.