idea for live show

[Routing Protocols]

invite the stars from the movie you are riffing.  sit them in the back of the audience.  Put a camera on them to show their reactions and let them riff you while you are riffing them.  Like if they had a sense of humor about it it could be funny.  they can be embarrassed or shake their head like theyre pissed or laugh or whatever and they can hold their nose when Kevin sings or boo when Mike tells a feeble joke.

[The Snape]

Hah! Now that would be a show but sadly it will most likely never happen. 

[RoninFox]

It really depends on the movie and the stars, but yeah, I don't see this as an easy task.  Even if the actor has a good sense of humor about him/herself and the work, there would still be some politics they might consider.  They might be afraid to lose work if they are seen making fun of (or going along with the making fun of) a director or previous film.  Not every actor is Shia LeBeoueaffe, willing to do interviews on how Spielburg or Bay dropped the ball.