I'm exploring using Neufville Digital's Futura as body text in a student workbook for learning a medical-software programming language. The text is broken into short one- or two-paragraph frames accompanied by Q&A and hands-on programming exercises. These short frames are designed to be read only one at a time, followed by breaks to program or answer questions. The text is set with plenty of interline spacing, 12/18, to help clarify Futura's less sturdy measures, and it's set ragged right to protect the word and character spacing. My hope is that these choices will help protect the color and texture of the page.
The code samples are set in Deja Vu Sans Mono, since we always program in a monospaced face, and the usual choice of Courier, well, . . . Since this a programming language that tends to be written in all caps, and since Deja Vu Sans Mono is darker and larger, I've set it 10/18, which brings it close to Futura Book's weight; I used the same inter-line spacing as the regular text to help protect the rhythm of the weave. The code samples are set off from the regular text by a hairline text box with healthy internal border spacing to help distinguish it from the text and to keep the regular text on its grid; the box is flush with the regular text paragraphs to help protect the integrity of the measure.
Within the simple structure of short frames, the text is difficult to set. It contains a mix of regular text, acronyms, titles of works, titles that include acronyms, code to look at, code to type, code quoted within the text itself (including alpha-numeric variable names), the names of keys off a keyboard (including escape and control sequences), formal terms from the system model, answers to be covered up until the questions have been solved, answers that include code, and so on. For such a complex text, my possibly misguided instinct is that slowing the reader down by emphasizing legibility over readability is the right way to go, with simpler, easier-to-decipher letterforms, figures, and punctuation. In programming, mistaking even a single character can cause the software to fail.
Nevertheless, I take seriously the frequently expressed opinions of Hrant and others that Futura is problematic for extended text. Therefore, I have two questions for this community for experts.
First, because this text is broken into short frames, and because it is intended to be studied and pondered rather than read briskly, does that exempt this text from the rule about Futura being unsuitable for extended text? If not, I'm certainly open to rethinking the book design; it's still in manuscript form and set in styles to make it relatively easy to change. I'm not looking for validation for what I've done so far. However, by the same token neither am I looking for a knee-jerk reaction against it. I'm searching for a way to make a difficult subject consumable in small bites and looking for the typography that best supports that.
Second, if we do stick with Futura I want to set it as well as I can, so can anyone point me to successful examples of Futura used for extended body text? For example, Bringhurst argues that Futura can be used as body text, but from my experience with it so far I'd concur with earlier posters who argue that it is challenging enough that perhaps it takes a master typographer to set well. Does anyone know of examples of Bringhurst himself (or anyone comparable) setting extended text in Futura?