I just want to know where the killer instinct is. I'm assuming that all of our veterans were, at one time, students of the game, watching Bird, Magic, Jordan, and Isiah routinely put the proverbial sword in the heart of the opposition at every opportunity. Did our guys not pick up on this or something? The said players knew all too well about the lack of margin for error in any series, let alone when it comes to beating a team without the homecourt advantage. Winning one game on an opponent's home court was hard enough, let alone three, like the Celtics are facing right now. Game 4 was a must win. It was not going to be easy, and they should have expected that. The Magic weren't just going to mail it in being one defeat away from elimination - they played out of desperation, the manner in which we should have approached this game. As we all know, the momentum can shift in a nanosecond - just ask the Yankees from 2004 or the Bruins (although I'm not a hockey fan).
Now, I realize that I'm overreacting (which is my nature, being a pessimist and all), but remember, Orlando became the first team in NBA history last year, despite the loss of KG, to defeat the Celtics in a series in which Boston led 3-2, so I don't think that it's out of the realm of possibility for them to think that they can come back (now that they have won a playoff game in Boston this year).
In the end, it always comes down to this: when you've got an opponent down, stomp on his heart and deliver the knockout punch (especially on your home court), don't give him a chance to get back into the game or series. As Bird said, "Push yourself again and again. Don't give an inch until the final buzzer sounds."