The celtics were 4-3 with Perkins as a starter, with 5 of those games at home. After the trade, the winning percentage was exactly the same at 16-12.
Also, people keep forgetting that Perkins did NOT play the first half of the season. So we were the number 1 seed in february despite having to work Shaq, JO, West, Erden, and Von Wafer in.
Finally, chemistry is great and all but it is not magic. Perkins didn't practice or travel with the team most of the time we were in 1st. Does he have magical powers to influence team chemistry form hundreds of miles away?