If we can assume it's a good book, and you've got a partner who has also read the book, with whom you can practice...
I think from a good book it's just as likely you can learn from it as a DVD. The problem with both is the lack of feedback to tell you if you're doing it right or wrong.
What must help is the right partner. If he/she can provide an alternative understanding of the material, or has different experience, this can only help.
Maybe a third person or a video camera would also be handy...
