Hey Ben,
 
The book is less about telling you how to play specific spots and more about telling you how to figure things out for yourself and how to think about the game in general.  For that reason, I wouldn't really say the book is "designed for" any particular stack depth, and I tried to choose examples with a wide variety of stack sizes.  That said, there probably is a bias towards short-stack situations for a couple reasons -- my own background is in HUSNGs and not cash, and also shorter stack situations are easier to solve or to study with a highly-analytical approach.
 
For example, Chapter 2 on strategic play discusses general concepts which will be just as useful for HUNL cash game players (or, indeed, any poker players) as for HUSNGers.  But in Chapter 3, when we first start looking at some real situations, we focus on the case of preflop-only situations: situations where players end up either all-in or folding before the flop.  This is a good way for everyone to start seeing some of the theory in action, but I also take the time to explore a lot of practical applications which are primarily useful for short-stack players.
 
Hope this helps,
 
Will