The author and your friend's story is amazing. I've never heard stories like this before, and they really impress me. I'm amazed at everything from his luck to why he stopped playing. All these signs indicate he's sensible enough to stop and understands the full risk he's taking. Although, after such wins, it's usually hard to stop, and we don't know what's going through his head; maybe he wakes up with that thought every day. On the other hand, I truly wish he wouldn't just play for a single bet, because we all know how addictive even a minimal bet can be, leading to the desire to bet more and more.