personally i tihnk it mite have something to do with the one piece, like mayb onli a member of a special group, one mayb luffy and aces dad or sometihng belonged to?
or it could b something special abt them, etc, ie y was Gol D Roger so strong, etc etc
i mean everyone so far in the series with 'D' is a very formidable character rite, mayb onli those that r most powerful can use it, mayb its something from the true history, if u get the one piece u can b the pirate king, wats more powerful than the ultimate pirate ship, mayb the one that was built for Gol D Roger, newayz thats juss my ravings,
thanks for listening
bye bye bye
Some cause happiness wherever they go, others, whenever they go