It's not an easy schedule by any means but these are the Celtics playoff/play opponents...
Minny, OKC, Atlanta, Charlotte, Atlanta, Miami, Toronto, Charlotte, Knicks and Orlando. Of their final 12, they play 9 of 12 against play in or playoff teams and the play in teams in the east this season are pretty strong.
If the Pistons go, lets say, 7-7, the Celtics would have to go 10-2 as I believe the Pistons win the tiebreaker. That's a tall task for the Celtics even with the Pistons not having Cade and it's not like the Pistons have been junk without Cade this season.