Sprints as described in Jake’s book are just like those in Scrum...and are not.
Using the Scrum framework for discovery is certainly possible, but Scrum’s deliberately limited set of constraints might not be sufficient during this stage when there are still so many degrees of freedom.
Enter the constrained design of the Sprint. As defined in this book the Sprint is highly structured enabling a laser-sharp focus on defining the problem, generating solution options, deciding what to explore, building a prototype and finally testing the prototype with enough real customers to get valuable feedback and learning.
While I do feel some discomfort with the apparent lack of opportunity for the team to self-organise, I see huge advantages in running a process that closes a real customer feedback loop in just 5 days (even 4 with Sprint 2.0).