According to Stephen Frail. the old model of textbook production was an editor and an author, working with for hire quiz bank creators. The new model, according to Frail involves many more people, "learning design scientists", and a more integrated creation model.
For David Wiley, all textbook creation starts with a faculty member "scratching his or her own itch" (a term borrowed from Raymond in The Cathedral and the Bazaar). The process is then iterative, involving expansions and refactoring. This has not changed much in recent times.
Usually, Wiley says, Lumen finds these peoplw who have already started to do that, somewhere in the "20,000 Biology faculty" is someone who has already started something. Of interest here is that Wiley is really seeing textbook production as a software model, and Frail is coming from a publishing model. This leads to a question: is courseware software or a publication? ------ Or, related, is the gaming industry a model? See Social Book