The bit where Steven Heller parallels design to be the circulatory system of the written word… well… genius.
An idea is the heart of every book; writing is its blood, and design its circulatory system. Design cannot be underestimated. A book that is merely composed according to a template, rather than with forethought and imagination, may be adequate for reading yet lacks the quality that makes savoring a book a complete experience. While a great text will conjure mental pictures, a great design—the marriage of type, typography and image—will give the reader added levels of perception that encourage cognition and appreciation. Even the most rudimentary design components—the texture of the paper, the kiss of a fine cut of type, the style of the running head or feet—are much more than aesthetic niceties. For this and other reasons the book must not only be appreciated, it must be revered.