Can Oscar Klefbom become an elite attacking defenceman?

The last time the Edmonton Oilers had an elite attacking defenceman, they blew it. 
First Justin Schultz was rushed into defensive assignments that were over his head, then he had defensive difficulties. Next, a huge faction of fans turned on him, the angry boo birds came out, Schultz lost his offensive confidence and there was little choice but to trade him away. 
The rest is Stanley Cup history.
Schultz was fourth in ice-time for Pittsburgh Penguin d-men this year. He has 11 points i