This is roughly how I think of it, though there are elements of both approaches that are useful in either area. The specific Agile methodologies (Scrum, XP etc) are more oriented towards development and production, so I find them less useful for discovery in any case. I don’t find it helpful to box discovery into sprints, or stories; the more important thing is following the principles. Are we iterating quickly, getting design concepts in front of real users and gathering feedback? Are we sharing information well, and adjusting our direction based on what we learn? Great, that’s what I want. The trappings of any particular approach are only important insofar as they help the team achieve those ends.