Favre was the keynote speaker at the LSU coaches clinic on Friday and told the story of how he learned what a nickel defense was. This was during his second season as a starter with the Packers, mind you. That means Favre was in the NFL for three seasons before he understood what the nickel (or dime) defense was.
Such things are trivial if you’re the gunslinger, though. Let’s be honest. It didn’t matter who was on the field. Favre had a cannon arm and he was going to force the throw in regardless (except when he couldn’t, but that wouldn’t stop him from trying).