Randols sudden change of heart

Also! Earlier, it's established that Nora doesn't buy Sheldon's "nice guy act." Further in their relationship, she expresses real surprise that Sheldon is in the biz for all the right reasons (she says something about "sincerity" being an easy disguise), and eventually she trusts Sheldon's lack of cynicism as genuine. That character evolution is mostly conveyed via Nora's winsome, suppressed smiles during live tapings, but certainly we can see it as it is happening.

Remember, too, how Randy, in disguise, kept trying to get Sheldon to badmouth him when they were in the car together? So Randy, like Nora, maintained his anger by fanning his own suspicion that Sheldon wasn't as nice as all that. (It isn't as well established, but then, Randy doesn't have as many scenes or as wide a window for character development -- that's a problem with the script, definitely.) But in that climactic scene where all three characters are finally in the same room, finally able to hash things out, Randy realizes his errors. There, he also approves of Nora's romance, promising her that he really believes Sheldon is the "real deal".

Maybe it's hard to believe Randy even in that scene, because he's still as histrionic as he is in all the rest, but I think we're supposed to. We're also supposed to accept that Randy's passions and motivations can change course from one second to the next, but his sudden and undying affection and redeeming act of sacrifice both rang a little tinny anyway. Maybe it's because we are, until then, always supposed to doubt Randy's feelings' authenticity (although we learn, in a too-short and too-late aside, that he wasn't always such a jerk).

Sorry for rambling! I'm not a big fan of the movie or anything, but I *just* watched it for the first time, and while I get what the movie was "going for," it really is sort of unclear as to how the gentle audience's allegiances are supposed to turn at any given moment.