This is interesting. I can imagine what Mandrake means about this debate surfacing often. Maybe there should be a bi-annual poll on this topic.
Anyway, I've been watching lectures all weekend(International Magic Convention) and I'm almost magicked out. There is a common trend towards talking about how good books are compared to DVDs. The Lecturer's would always talk about how they learned from books. And then, they bring out their DVD's to sell

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By the way, I like both. With books, I specifically like kids magic books. I like building a routine around them. Books that explain complicated moves tend to bore me. I'd rather watch them from a DVD. Bottom line for me is the value of the effect not the sleight. I'm not too good at sleights.