Big 3 Celtics - Worst Closeout Team Ever

[BattleTested]

Celtics record in closeout games-
2008 - 4-3
2009 - 1-3
2010 - 3-5
2011 - 1-0
2012 - 2-4

Overall, in games in which the Celtics could close out an opponent and move onto the next round, they were 11-15. They were 55-38 overall in the playoffs during this stretch. That means, they went 44-23 in non elimination playoff games through the big 3 era. They were dominant, they just couldn't close out teams. They blew three 3-2 leads during this stretch, two of which resulted in championships for the team that came back. They also let an Orlando team that was down 0-3 get a 6th game.

So I have two questions:

1. Is there any team in history that was nearly as bad at closing series' as this team was?
2. Why were they so bad at delivering the knockout punch? Was it because they overachieved to get the leads in the first place? Were they just old and prone to fatigue later in a 7 game series? This was a tough, championship core. It doesn't make sense that they would let teams off the hook so consistently.

[JordansBulls]

For a team that was good enough to win the title, I can't think of any off hand. Maybe the Sixers or Lakers when Wilt was playing. I know they were up a few times either 3-1 or 3-2 and lost the series.