I haven't weighed in on a subject here in quite awhile. May as well be this one.
I would say that it would have to be very basic, very easily correctable, and if not corrected the bad habits that develop wouldn't damage the knowledge being gained. Meaning for example, your goal was a simple straight palm running up an opponent's centerline wouldn't necessarily be bad even if you fish tailed a bit.
That boils down to simple self-defense techniques, not an entire "system". With a strong will, self-discipline, corrective practice you would be able to learn the basic details of techniques, but how much? How much better would you be with an expert instructor viewing and correcting your techniques just one time a month? Imagine 2x a month so correction to bad habits could be stopped almost imediately instead of breaking them and having to relearn?
The issue I see isn't that video is a bad media to teach students, it is but a single tool that should be used in the over all picture of gaining knowledge. What I see happening is a lot of instructors and students are seeing it as the "all in" method of learning. This is where having years of experience will help you. This is how video can help you gain knowledge when you are unable to experience it first hand.
Learning from scratch? I will say no. To many fatal errors can be made in a single jab or jab/cross combo, how many errors are going to be made in a full on Kenpo Technique (even if it has been stripped down to the bare basics for ease of learning)?
Experience is a great teacher. Because I watched "Saving Private Ryan" does that make me a combat vet, even if I watched it 100x and practiced the combat rolls, low crawls and markmanship?
Until you feel it, it aint fricken real.
I am a video student, I also am lucky and have access to some quality instructors, I also have nearly 15 years in the game. I am also a "Live" student. Meaning I get bruises and bloody noses when I make a mistake, not a tape saying try it this way.
