Although I can't say that Marquand, if left to himself, would have done a great job anyway. I specifically remember an interview with him where he said he "wasn't going to make the same mistakes Kershner made." His example was Darth Vader holding his lightsaber with one hand when he began fighting Luke on Bespin. "Everyone knows a lightsaber is too heavy to hold with one hand!" That is a Marquand quote.
Even at 15 years old, I knew he wasn't getting it - Vader was holding the saber with one hand to demonstrate that he was being cocky and UNDERESTIMATING Luke - later in the fight, when he realizes Luke is a greater foe than he realized - he's not just holding the saber with two hands, but he's feverishly fighting for his life!
THAT is brilliant direction. All hail Kersh/Kurtz.