Interactive Video Content

That's an interesting one. I'm thinking you'd have to start your timeline with triggers to show both layers and have them set to not hide other layers. If you don't want both videos visible at the same time, you'll have to cover them up with shapes or images.

Even if this works, if both videos have audio, they won't be perfectly in sync. Storyline activates triggers one at a time. Sure, really really close together, but still one at a time. The delay between each layer's trigger might be enough to create a noticeable echo with the videos' audio.

If you try it, let us know what happens!