Since 1990, here is how #6 seeds have fared by round

All-time playoff record of 6th seeds is 31-52
1st round games vs 3rd seeds is 23-33 (41%)
2nd round game vs 1st seeds is 5-17 (23%)
3rd round game vs anyone in CCG is 2-2
Super Bowl vs anyone is 2-0 (100%)

The five #6 seeds who won a 2nd playoff game:

2005 PIT, won the SB
2010 GB, won the SB
2008 PHI, lost in CCG
2008 BAL, lost in CCG
2010 NYJ, lost in CCG

one of those sixth seeds got blown out by 42 points that year by the team they met in the 2nd round of the playoffs.

NYJ got smoked 45-3 by NE in November in NE.
two months later, they went into NE and beat them in the 2nd round.

AND, each of the other five #6 seeds who won a 2nd round game,  lost in the regular season to the team they played in the second round.

If Sanchez and Rex Ryan can beat NE after getting smoked and the other four can win the rematch after regular season losses,

THEN So can the Super Bowl champion Philadelphia Eagles!!

Gotta Believe!