Yeah, that was glaringly lacking in the post. I doubt the idea is one that no one's ever thought of before and keeping it a secret is only going to prevent him from getting potentially valuable feedback.
Absolutely agree. I was looking for feedback and encouragement/doubts from people who have done this before, so I left it out intentionally so I could do a follow up post focusing on the idea itself. Several users in this thread have guessed it already though.