The 76ers actually is the real champ of the Atlantic division.
They messed up some games during the regular season but their winning DIFF 4.2 compared with Boston's 2.5 indicates which is the better team.
Won't be surprised or calling it an upset if they won game 7 in Boston
A 4.2 winning DIFF for an 8th seed is very rare to see, here I am comparing this year's philly with some other 8th seeds from the past:
1994 nuggets 42-40, diff 1.5
1999 knicks 27-23, diff 1.2
2007 warriors 42-40, diff -0.3
2011 grizzlies 46-36, diff 2.3
2012 sixers 35-31, diff 4.2
These teams didn't knock out the first seeds for no reason