NeverarGreat said:
Again, that’s just my opinion of the scene. It’s certainly possible to read this as Luke conforming entirely to Jedi doctrine, but since he had already started down the dark path and was able to return, one of Yoda’s teachings at least was proven to be false.

That was already proven false with Vader himself. The big thing you see throughout RotJ is that Luke has a different outlook on things from his former masters and his peers. He’s shown to believe that you can come back from the darkness. His masters believe that Luke is the only thing that can defeat the Empire, but Luke trusts the rebellion to be able to succeed without him. That’s why he went with Vader instead of staying. He thought he did more damage to be with them than he could prevent by being an actual superhero. If he didn’t believe his friends could do it, he wouldn’t have gone.

Overall, he’s much more trusting of the Force to work in its mysterious ways. When he’s shown attacking the Emperor or Vader, it’s shown as him having doubts that his friends would succeed, fear that he’ll lose someone. Luke’s Light is different from the Prequel Jedi (who are again supposed to be corrupt Zealots). He’s not without emotion; he’s quite passionate even without it looking like he’s using the Dark Side.

Lord Haseo said:
You don’t think he can adopt a philosophy of “Use your inner darkness to best your enemies but don’t let it envelope you for too long”? Also what’s to say that Luke didn’t take bits and pieces of philosophy that Dark Siders hold dear and use them to bolster his new philosophy?

To me? No. Again, I still see the Dark Side as the malignant tumour on the energy field that life creates. It is not a difference in philosophy; it is the manifestation of the emotions behind bigotry and oppression. Being “A little dark” is akin to being “a little evil.”