Well, i've seen this too, not only with Go but with Programming and a whole lot of other things. They're busy showing off how good they are, instead of helping you learn.

However, once you know the trick, you don't need anyone to teach you, but just someone you can imitate. Just get them to be quiet and play lots of games with you, or ask them questions when you really need to know something. Be the driver of your own learning, then your teacher's teaching skill matters less.