Man, when there's something similar that proves Garp might not use advcoc, you want me to ignore it?
Oda has used black lightning many times for normal fights why is it only advcoc in one fight?
Oda Just Drops a Joke A man who fought a pirate king to the death needs practice to defeat a common pirate.
I've never seen anyone need advcoc for practice, if they use this ability in aokiji's flashback, I'll accept my L, otherwise your argument is wrong.