<< If you take into account the pre-Byrne era, he was able to fly faster than light. >>
That's ALL I take into account.
(Guess that makes the Byrne retcon 'no account' eh?)
Not only could Supes go translight, he could do it effortlessly. Didn't even need a running start. Remember when Ambush Bug hitched a ride by *bamfing* onto Supes as he hit light speed? IN THE AIR RIGHT OVER METROPOLIS?