For me, the thing I like about this idea isn’t that it preserves the twist, but rather it almost totally eliminates the problem of Anakin’s sudden turn. We, as the audience, are with Obi-Wan when Anakin turns; we don’t know what happens back on Coruscant. We are with Yoda when Obi-Wan goes to fight Anakin, we only get to see Obi-Wan return with Padme in his arms. We’re left to wonder what happened on Mustafar. Even if the hypothetical first-time viewer knows that Obi-Wan trained Anakin, and that Anakin becomes Vader; they still have the luxury of piecing together what exactly happened on Mustafar as the OT progresses.