This bugged me the other day. It's so painfully obvious I never thought about it until now.

The CLIMAX of ROTJ is Luke throwing his lightsaber away, rejecting violence, and taking his mantle as a Jedi.

Luke is not stupid. He beat Vader, refuses to kill him, and apparently thinks he won.

This is great... but it hinges on the fact that neither Yoda nor Obi, both of whom have first hand knowledge of how this works, mentioned to him that the Emperor can shoot freakin lightning, and Luke could block it with his lightsaber.

Just one more way the PT totally drops the ball.