What was a bit offputting was how quiet Colbert was when the camera was not running and how much more energetic he was when it was. I know they are playing it up for the camera, but it does make it feel ungenuine.
And add to that the format of the talk show. Each of the guests sorta comes up with a routine, planned by their publicists. If all goes well, they get their message across while being spontaneous. A hard thing to do, but also something that feels authentic. It's not just two buddies hanging out on TV.
You also realize that the TV audience is by far the most important part of the filming process. You're just a setpiece.
I'd almost say don't go to a talk show taping if you like them.