If you mean when a timeline meets a keyframe action in the Timeline view. Then no.
You can preview in the browser but not inside hype. I think many of use would like something where we could preview the full flow of the timelines but cannot imagine how it would work if multiple timelines and actions.
Maybe if hype had it's own browser option for preview. When you run in the Hype browser a floating panel pops up that shows a visual list of all timelines and actions (kinda of like Activity Monitor.app) along with being able drill down into them for more detail of whats going on..