A similar though "minor" version of this style is a letter like The Panic Puzzle Program | Overcome Your Anxiety, Fear, and Panic Attacks
What's been your experience in conversions for this style of copy? (I know the best way to find out is to test.) Have amazing samples to share? Have tips to make this successful?
The principles of good copy don't change. I know you also need to be careful at keeping everything relevant to the product/service being sold otherwise you'll distract the reader.
The benefit I see of it is it may not trigger the "oh crap, another site selling something to me" response. And readers can jump to the information that's important to them (like testimonials, samples, or ordering) as everyone is at different stages of the buying cycle.