When I was a young man I would have laughed at the idea of using videos for training purposes. My idea was that you should just go to class and practice and that videos were not really worth much in the realm of training. However, today I am of a different mind. Maybe it is that I am older and can't remember as well as I used to or that I have a career and cannot dedicate my time the same way. It is probably a bit of both.
I ordered a couple of DVD from Master Tatum's collection, mostly to help me associate the names of the techniques with the movements. I really find them to be excellent. They do what I want them for - reinforcement of class - and they offer more. Specifically, Master Tatum offers some tips on the execution of the techniques, purposes for kata, practical applications as well as how the technique is supposed to look.
A part I overlooked before is that it motivates me to work on techniques more at home. This will make me exercise more and hone my techniques outside of class. This is a great benefit. So I would recommend the dvds and find that they help me in many ways. Great!!!