In television production, a teaser or cold open is a short sequence that runs before the opening credits. Teasers are designed to grab the audience's attention, usually (for narrative shows such as sitcoms and dramas) by setting up the plot for the episode.
For shows with multi-episode story arcs, the teaser is often a recap showing scenes from previous episodes. In most other shows, the teaser (if any) consists of original material. Usually this material is scripted and shot specifically for use in the teaser, but as Cheers writer Ken Levine explains, sometimes teasers are repurposed scenes that had been cut during post-production from overly long episodes. But even in that case the material is "new" as far as the audience is concerned.
In a minority of shows, the teaser is neither a recap of past episodes nor entirely new material. Instead, it is a sort of miniature "clip show" consisting of one or more scenes from the main part of the current episode. An example of a show using this kind of teaser is The Flintstones.
Is there a term for this kind of teaser? Also, in scripted shows, who decides which scenes get shown in this kind of teaser? Is this something that the screenwriters include in their scripts, or is the selection made by the director or editor in post-production?