I am not trying to be difficult, but some of this editing doesn't make sense to me. The three issues raised are profanity, violence and dead space (slow/boring) in the movies.
1) Profanity: I am not sure who dubbed over the word f**k in "Amanda and the Alien". If it originally aired on Showtime, they would not have edited it. And, it makes no sense that Rifftrax would edit it out since other VOD's (ex: Mind Ripper) have the F-word unedited. The only thing that makes sense is the movie was re-broadcast on another channel that dubbed the cussing, and Rifftrax used that copy.
2) Violence: What violence would Rifftrax edited out, and why? Can anyone provide a specific example in any movie?
3) Slow/Boring: The first two movies that come to mind when I think of nothing happening are "Birdemic" and "Rock-n-Roll Nightmare". Both have long, boring intros. Neither is cut short. "Birdemic" runtime is exactly the same, and "Rock-n-Roll Nightmare" is 7 minutes longer on Rifftrax. If those movies aren't edited for boring scenes then what movies are? Any specific examples?