It's not a case of proving the concept, it's proving it works all the time. If I were to use that, I'd want to know there was as close to 100% success as possible on it. Otherwise I'd just be wasting my time. Oh, 11 people said it was ok? Yeah, and 99,000 people said it was ****.
Gonna have to do better than that. How many people have actually used it, do you know? Then you can see what sort of ratio 11 is. If only 11 have ever used it and they've all been successful, you got 100% success, if not ....