It's an idea I just threw, since I found the picture of Anakin watching the space visually powerful, and OTish. Think it would give us some certainty that infact, Vader has much of the "old" Anakin inside him; by seing some continuity in his gestures through the Saga. What's more, in my message I say this shot should be somewhere in the PT, and not only talkin of EPIII. However, EPIII is the best choice since we got the most grown and mature soldier. Not Anakin the boy, nor the apprentice, but the brillant commander.

It's true that there's no room in the plot for something like this... perhaps you could have Vader go to Mustafar by star destroyer... though it would still be Vader(non suited) and not Anakin.

There's no argumental justification for this shot, but the visual signification it has. The idea came to my mind and had to share it with you.