He remembered it with ALL of the pieces displayed before him in the newspaper . Sakazuki means sake cup , Ace and Luffy were both mentioned in the newspaper covering the war . I think it was a fairly reasonable way for him to recover the memory . Amnesia as a plot device isn ' t poorly used by default . It ' s a very common trope , but you could say that about many other things used in One Piece . PAs an aside , are you familiar with the rule of three ? Many things in literature tend to follow this pattern of things being grouped in threes . Many of Oda ' s own characters are grouped as such as well . Other than ASL , there are the 3 Admirals of the Navy , 3 great powers ruling the sea WGMarines , Shichibukai , and Yonkou , the Straw Hat Monster Trio , Weakling Trio , etc . I would have expected a third brother , honestly , even before his introduction . I ' m not arguing that he was thought of before his true introduction back in the Summit War Saga , but his introduction and the way he has been used in the story so far aren ' t poorly done in my opinion .