I'd be very cautious of role-based navigation. When working on GOV.UK education content we found that users can fall into multiple categories and content for one group was more suitable for others (eg teachers reading content for parents as it was easier to understand than offical DfE policy docs)

A task-based interface works much better IME, which is what Airbnb is doing "I want to host" v "I want to rent". I haven't read the book yet, so might be missing the point here.