I'd love to give this one a five, because it's pretty darn awesome, but I can't. I've gone through this and, while it's most definitely a problem on my end, people have commented correctly on the secret.
Of course, this is entirely my fault, but here is my advice. When you do this effect: ALWAYS make sure they're watching when you pull the key of the rope. They must be watching or the whole effect will CRASH AND BURN.