Your seeming to forget the high level master are capable of moving and hiding their chi from those below their own levels ? Every mopai students are taught to do this, in fact john chang does it when he will visits china and abroad. He will tell you he is not capable of detecting teachers of a much higher calibre, but is only at his levels close or similar to his.
Do you forget the stories about the golden light challenging master chang and defeating with him ? Were you aware this man lived in the same town and was only reminding to remain humble ?
Kostas books are not neikung bibles. You must EMPTY YOUR CUP as bruce lee says.