You have to have a truly elite defense for them to carry the team to wins single handedly without fluke plays like pick 6/Fumble return TDs. I mean a truly elite defense. IMO, you can't have that without an absolutely dominant DL and solid players in the secondary or a very good DL with an Elite FS/CB/LB combo. It's probably been decades. To be honest you rarely see that good of a defense on any of the 32 teams. In recent memory the Bears, I think around 2006-2007 led Rex Grossman to a SB and the early 2000s TB team that led Brad Johnson to a SB come to mind.
If your premise is a defense capable of being a huge factor/the main factor in a 2-3 game stretch the 2nd or 3rd year under Wade was good enough to do that. To actually depend on a defense to practically singlehandedly carry a team, even for a few games? Thats going to go way back.