Inserting

The difference between an overlay and an insert edit is that inserting makes the video longer and it does not interrup the sequence of the main clip. You would use an overlay when you want the video to seem more realistic in sence of time, while you’d use an insert edit when wanting to show the whole clip when inserting something in the middle of it. In this case the overlay edit works better because it shows the video continuously and it makes more sence in terms of time.