Han did not shoot first, you sad, sad fanbois.
"The controversy over who shot first, Greedo or Han Solo, in Episode IV, what I did was try to clean up the confusion, but obviously it upset people because they wanted Solo [who seemed to be the one who shot first in the original] to be a cold-blooded killer, but he actually isn't. It had been done in all close-ups and it was confusing about who did what to whom. I put a little wider shot in there that made it clear that Greedo is the one who shot first, but everyone wanted to think that Han shot first, because they wanted to think that he actually just gunned him down."
Not he thought twice about it and wanted a digital mulligan. Nope, instead it was in the original scene all along.
He doesn't like his fans very much.
More to the point, I never saw how it made Han a cold-blooded killer anyway--he's being threatened with a gun, and the thug's about to pull the trigger.