They used either the 2-1-2 or the 1-2-2 for most of the regular season. The 2-1-2 and a trap scheme are typically used somewhat interchangeably, depending on the specific rush and the game state. Almost no team (save perhaps the Tortarella-era Rangers) use the 2-1-2 exclusively, but rather, they commit to a 2-1-2 when there's a legitimate chance to force a turnover (or when the score dictates that they need to take risks in order to create turnovers). When the other team has a clean possession in their defensive zone, most teams will use a less aggressive forecheck (trap), such as a left wing lock, 1-2-2, or 1-1-3.
Even if you go back and rewatch the Guy Boucher Lightning, who were famous for their zero pressure 1-1-3 variant (effectively a 0-1-1-3) , they would read the play and decide when they could go with a 2-1-2 instead of the 1-1-3. In my estimation, it was the Lightning's 2-1-2 attack (or minimally the alternation between the 2-1-2 and the 1-1-3) that gave the Capitals so much trouble in the 2011 playoffs, not the 1-1-3 alone. Boudreau couldn't create a breakout scheme that could react appropriate to both style's of Boucher's attack.