I predicted 28 wins in the other thread.
Rondo in or out has not made that much difference in wins and losses over the last few year. I think 28 wins whether Rondo plays out the year or we trade him. Any big trade that occurs mid season usually results in some backwards development so if Rondo or other key players are traded, even for better players (which is unlikely), we probably lose a couple more games as a result but no big swing.
I don't know what formula the Geeks use but in this case, seems about right to me.