When I rang the Stones’ doorbell the following afternoon for our next research session, I felt my knees unstable underneath me. Janis had coached me through what to wear—a plain gray t shirt and some reasonably nice jeans. “Don’t look like you’re trying,” she’d said, rolling her eyes. “You’re hopeless sometimes.”

“I’m always trying,” I protested, knowing it was true. I always tried my hardest, no matter what challenge was in front of me. It’s how I ...