When the Vikings signed Brett Favre in August, there was no shortage of criticism and negativity from those who supposedly know it all.He's too old. He's got no gas left in the tank. His arm will fall off. He'll fade late in the season. He'll be a cancer in the lockerroom. He's a prima donna. He only cares about himself. He and Brad Childress will hate each other.While watching Favre have one of his best seasons ever has been thrilling, I've gotten even more satisfaction just thinking about how frustrated all those know-it-alls must be. JESSALYN HINZ, RICHFIELD