Effective knowledge transfer
Which is more effective: a lecture, or a tutor?
One-on-one knowledge transfer works way better than trying to teach everyone at once, and we all know it. Lectures are an unfortunate necessity of having too many people to teach in a small amount of time.
That means that if you have a small enough group to teach, lectures or video recordings should not be anything but a last resort. Keep things small and targeted for as long as you can.