The Saint's safety used to play with Favre (or against him regularly, I'm not sure). Anyways, having a safety and QB who are very familiar with each other will benefit one team more than the other. My guess is its the safety who can tell his teammates about Favre and make better reads.
Brett Favre is 40 and playing very well behind an excellent offensive line. What does that mean? A good offensive line means even a 40 year old can make the playoffs and pro bowl. A bad offensive line and no QB, no matter how talented, could make the playoffs.
Did the Colts create a monster by laying down against the Jets?
Only time will tell!