Well, if there are or were locker room chemistry issues, specifically involving Rondo, it's mostly the Big 3's fault. I love each of them till the end, and they are HOF players. Paul is still my favorite Celtic, and KG is the heart of this team. That being said, Rondo is now the best player on the team. If there are chemisrty issues between the Big 3 and Rondo, it probably stems from the butting of heads over control of the team as far as who initiates the flow of the offense. Plain and simple, the Big 3 need to get over it. This team is best when Rondo leads it.
Luckily, it looks like they have gotten over it.