I read this one as well and I kind of liked it.
There are many points backing this up and it also explains lot of things about BB.
Xebec in historic sense means
3 masted Mediterranean ship. BB ship is named Xebec and we know there is something going on with number 3 with BB -
- 3 skulls on pirate flag
- 3 bladed claw
- 3 scars he gave to shanks
- 3 Dfs
- when Oda drew that historic panel (below) notice that we had 3MCs of One piece which oda said are most important and also the first 3 to join - Luffy, Zoro and Nami.
Then it kind of fits in with BB having different personality and why he never sleeps and how oda loves to draw parallel between past and present.
I was also curious about why we only got Xebec silhouette and never his real face.
Another thing is BB was born two years after Xebec's death so one can say Xebec is in BB because of some df like Brook (different version) which points (if true) to
- Why bB hasn't gone after third df because he already has 3 dfs
- And, why he knew about yami from so young age