[ig1]

Your attack relies upon security by obfuscation, hoping that no-one will notice that the behaviour is incorrect (we obviously disagree about the chance that such an attack will be spotted but I think to some degrees that's irrelevant).

The RNG attack has correct behaviour under every statistical and blackbox analysis. The only way you can break it externally is if you have the key.

If you were designing a cryptosystem you'd pick the one where the security lies in the key and not in obfuscation. The same applies when designing an attack you want to keep secret.