Yeah, I agree with the PP.
I think there's a distinct chance CK melts down. Yes, I was there for the first Eli Manning at the Clink game, and remember the bravado in the media for the days leading up to the game, and saw the complete and total meltdown on the field... It would be very surprising for CK to remain upright, put it that way.
As the PP noted, the 49ers, by virtue of the coaching decision to start CK over Alex, have had a bit of internal turmoil already this year, and with the personality of the head coach, there could definitely be a big storm of emotions and finger pointing if CK has trouble.
That's actually my dream scenario. We destroy the CK led 49ers because they can't function in the Clink. The 49ers manage to defeat the Cardinals, but end up switching to Alex Smith either before or right after that game. We get to play the 49ers in the second round of the playoffs, and defeat the Alex Smith led 49ers in Candlestick.
(Though I'm also OK with defeating the Packers by more than two points at Lambeau.)