Jesse Ventura said it best when he said "Politics is a lot like professional wrestling. They appear to be enemies in the ring but behind the camera, they're best of pals."
That being said, the Republicans have to walk the party line and scream "Do away with GSEs" and the Dems have to say "No way!"
I'd be willing to bet that they already know what's going to happen, but the show of the fight needs to play out to satisfy voters.