Ok. Promise you won’t admit this to your filmmaker buddies. For most online educational videos, if we film in 1080 definition we have a degree of wiggle room to ‘zoom’ in a little when editing stage when needed.
That is if we need to splice a paragraph-worth of speech from one take with a paragraph from a second take we can simply ‘zoom’ by expanding the size of the clip within the given ratio and select an appropriate unobtrusive transition such as a cross dissolve (‘barn door’’ transitions are never good).
On the subsequent splice you can ‘zoom’ out. Used sparingly this creates the illusion of an intentional storyboard choice rather than an obvious blooper splice. To be effective, cross dissolves require sufficiently different data in the two clips to be joined. That is if you zoom in only slightly with the presenter in the same place, the transition will look blurred and awkward.