Does Perk's presences on the court butterfly effect away Wade dislocated Rondo's elbow?
That's the biggest factor in my answer.
The Celts keep Perk in 2011 and they probably maintain the #1 seeding in the East that they occupied when Danny screwed the team up by making this trade. thus, they don't play Miami in the second round and Rondo doesn't get hurt.
As for the 2nd poster who says "you haven't watched Perk play much recently" - you are yet another among the hundreds who just cannot get it thru your collective thick skulls that what Perkins did for the Garnett-era Celtics a) was not usually going to show up as big numbers in a box score and b) was invaluable to the defense and toughness that those teams thrived on. the team was never quite the same after that trade.
Perk's style was much more effective for the Celtics than for the Thunder - he was essentially a better player here because his skills matched up with the Celtics playing style and team persona. The Perk-Green trade was the football equivalent of sending a very fast, athletic wide receiver to a grind-it-out run between the tackles offense and then sending a huge straight ahead, road-grading offensive lineman to a finesse spread option offense. Neither player is going to excel in a system that doesn't utilize their strengths and abilities.
Danny once again tried to prove how clever he is and in the process threw away an excellent shot at # 18 that season. he convinced himself that we needed to be more like Miami and Chicago (small-ball finesse) instead of maintaining the defensive-minded, physically tough style of play that gave us the one advantage that no other team had over the Heat and Bulls.
finally, Jeff Green is a nice guy and a nice player who will never lead us to a title - he has athleticism in spades, but lacks mental and physical toughness. it just ain't in him.