I'm fairly new to Tai Chi, learning my way through the Cheng Man-ch'ing short form at classes. I'm delighted with this DVD. The video coverage of the different postures is first rate, as are Angus Clark's explanations. I'm finding it very useful in helping me to pick up on points that I've missed or misunderstood in class (easy to do when you're trying to follow a teacher and just make it through something new without making a total mess). Inevitably there are the odd, minor differences between the postures as played by Mr Clark and as taught in my class - but even that's useful; I'm finding that thinking about the differences is often informative in itself. I definitely feel that I better understand the postures I'm being taught; I suspect that the way I play them is improving faster by consequence; and I know that it's adding to my enjoyment of the whole experience. Well worth the money I spent.
(And whilst there's undoubtedly no substitute for a good teacher to pick up on your faults, explain what the different moves are and why you're doing them, and ultimately help you move beyond rote imitation - I'm sure that, yes, you could learn to do quite a good approximation to the form from this DVD.)