It's not insider information. Phillip Rivers himself said it when he was being interviewed by Rich Eisen and the NFLN crew postgame at Denver.
He said something to the effect that people criticizing his game was overblown and didn't have merit to it. Which is what NFL fans do all the time.
Again this whole notion that someone is going to come and teach Stafford or Rivers how to throw a ball is ridiculous because they are the best in the world at it. What will help Stafford is Whisenhunt's playcalling and not putting Stafford in situations where he has five receiver sets, and the defense knows we're passing the ball.
That and getting him some decent receivers who actually can catch a football. Its not a coincidence Staffords best year, and playoff year in 2011, is when we were loaded with talent at the WR and TE position.