User blog comment:Monkey.D.Me/WAS HE NEEDED??/@comment-4311127-20111211031641/@comment-3075024-20111211054441

What I mean to say is that even if Oda did now show us Luffy's past with Sabo in it. The One Piece would be same to what it is. I am sure that Oda thought of adding Sabo after the Thriller bark Arc.