You take a game where players were missing or injured, ignore the unusual way the game started, and then fail to remember that the Patriots had been coming off of a very emotional and physical game while the 49ers were coming off of games against the Rams and Dolphins. The Patriots have held 5 of their last 6 opponents to under 20 points, and that includes a shutout. They're not a great defense, but that's certainly a pretty nice way to be heading into the playoffs.
Selective memory seems to be something you're familiar with on this topic... How'd that SF team do the following week against the Seahawks? How flat was that Seahawks team the weak after they played the 49ers?
Welcome to the NFL.