I doubt the Eagles are going to win at the current pace. They won't go 15-1, that's for sure. But expecting this team to just implode like last year's would be foolish IMO. They had some really big holes last year - no WRs, no running game, awful CBs and despite a good front four, they had issues pressuring QBs later in the year.
They have real WRs this year, they've shown they can run the ball much better thus far, their CBs are still weak IMO but with Darby, it's better than last year's crap they had (including everyone's favorite, Nolan Carroll) and they are better at getting after the QB this year (Jernigan at DT has been a big improvement on Bennie Logan who was more a run stuffing DT).
If the Cowboys want to win the division, they are going to have to go on a big run because expecting the Eagles to spit the bit and go from 5-1 to 9-7 would be some real wishful thinking IMO.