professor
I think when it's an impressive defense, as in recent years with Seattle, Denver, etc., then absolutely - those types of staunch defenses can help deliver rings. Maybe I'm wrong in my perception, granted... but in no way do I see New England's defense resembling anything close to that level of absolute physicality and coverage.
They will obviously be head-and-shoulders stronger than Green Bay, just out of respect to being healthier alone, but I still suspect it will ultimately come down to how well Ryan and his receivers handle the pressure of performing in the Super Bowl. If NE can't get pressure on Ryan, then I suspect they'll have their hands full.