The ground can't cause a fumble is a major misnomer. Just think of when Eli slid head first and fumbled...the ground obviously caused the fumble but he was never down.
The statement simply means that if the ball comes out after a person's body touches down, then it isn't a fumble.
Eli's play was like Griffin' of a few years ago. When a QB gives himself up the ground can in fact cause a fumble. Last night was like the Ernest Byner fumble against the Eagles in that playoff game. In both cases I believe the ground can't cause a fumble on a player who is being tackled.
Absolutely. Have to look at context.Passer rating can be an overrated stat because KC failed the eye test last night.