Isnt the author, well, supposed to keep his private key private? It was quite easy to create a text file with that 1b0be2162cedb2744d016943bb14e71de6af95a63af3790d6b41b1e719dc5c66 key and "geth account import key.txt" into a ethereum wallet to get a seemingly valid account. Please tell me that i am missing something very important here.