Until the end, I thought you were talking about web cam videos.

Since that's not what this topic is about, I'll change the thread title slightly and stay on the topic at hand.
Personally, I don't think its necessary. Especially the street either. Sites like E and T11 really do put their EVERYTHING into the DVD's they do. So live street performances really are gifts. Sankey sometimes has an assistant and other magicians sometimes still do that or as you said, a quick performance for the camera. A performance for an assistant at least is nice. However, magic DVD's are meant for their secrets, not entertainment value. Any more than a quick performance for the camera is optional really. Is it nice? Yes. Is it a necessity? No.
-Doug
To be honest, I think that the fact that it is not considered a necessity is rather shameful. Whatever happened to the good days of magic, where only experienced magicians put out material - and when the ad copy said, "from personal repertoire", it actually meant something? It meant a lifetime of work - years and years of research and refinement.
Obviously, a huge part of magic is its presentation. I believe that you cannot learn all the nuances of the effect without watching the creator perform it for real live people. It's all very good to tell someone to say this in this situation, and pull this sleight at this time, but it's very different to actually seeing the master at work.
Unfortunately, I think the standard of teaching magic has dropped, and hence it is no longer considered a necessity. The creators do not know how to teach magic, and as long as the necessary sleights are taught - this is the standard that people are happy with, which I think is sad. Now, it is good enough to simply teach the sleights, show how it will go, and not teach nuances. Not teach history. Not teach the
performance but merely the secret - essentially, teaching half of what should be taught.
Take Kard Klub for example. The value of that DVD is in the criticism of numerous street presentations. And there are lots and lots of it. In my opinion it is worth more than any of the other E DVDs. That will help your magic and improve your magic MUCH MORE than any collection of tricks and sleights such as Ninja and Crash Course ever will. Lots of young magicians grow up to learn the secret, not enough know how to present it. Many tricks could be so much more, but people are simply happy with great reactions when reactions could be
unimaginable.
This, as I have said, is simply a dropping of standards, and for this reason I disagree Doug.