@brennen.exe:
[[I]I removed all of your conjecture up to your main point] What if what he wanted was a war between the Marines and Whitebeard?
I think so. He knew the protocol for dealing with traitors, even if he did not know that he was going to be let off, but if Whitebeard survives this war, you bet there are going to hunt him down, but he's planned for that. So, you once did a flowchart of his scheme, I think this one will do:
! 1. Get the Yami Yami no Mi.
-Status: Succeeded.
! Well, we know this part, so let's not gloss over it.
! 2. Start own crew.
-Status: In progress.
! Doing pretty good so far on this one.
! 3. Become a Shichibukai
-Status: Succeeded, but not in the way he thought of.
! So, why does he want this? For the benefits, like privacy and allowed to sail around unharassed by the Marines as he builds up power. So, if there wasn't a spot open, he'd probably go find a Shichibukai and kill him. But, as luck/fate would have it, a spot was opened, and capturing Luffy, the man responsible for it, would get him there, but as luck/fate would turn out….
! 4. Capture Portgaz D. Ace
-Status: Succeeded.
! So, after becoming a Shichibukai after taking in Luffy alive, and Thatch dead (I imagine he cut off his head, and was saving it for the job), he'd then turn his focus on the man sent out to take vengeance on him. However, Ace came first before Luffy, so he captured him instead, and used both bounties of Whitebeard's commanders to get in.
! 5. Just before the battle starts, sneak into Impel Down.
-Status: Succeeded.
! Blackbeard should know how strong his old Captain was, so I imagine that Blackbeard thinks he'll win, so he sneaks in with a Marine battleship to get close, and gets in.
! 6. Free everyone on Level Six, and as much other prisoners, pin this on Magellan.
-Status: In progress.
! Now healed up, Blackbeard will be off to get Level Six free, and his men armed with a bunch of Hydra Antidote, saving the lives of hundreds of escapees cut down by Magellan. He gets them on a boat with some dead ID guards, rounds up what's left of the guards, and sneak attacks and takes down Magellan. Once the battle is over and the Marines come over, he pins the blame on Magellan and his so-called incompetence, saying he just wanted to help, and sucker punched him. During this, the ship breaks out, which he insists he got them under control, with no help from Magellan, and he somehow manages to succeed, with more probation, or whatever.
! 7. Get the ID escapees to Fishman Island, where they will draw out a weakened Whitebeard and kill him.
-Status: Pending.
! Well, I think the title says it all.
! 8. Spend time killing what remains of the Whitebeard Pirates, and biding time and strength, and more crew members.
-Status: Pending.
! Now, just kill off the stragglers until the Supernovas start getting some real steam, then....
! 9. With the absence of a Yonkou, and the Supernovas breaking out, aid the Marines in a all-out battle between them the remaining Yonkou, the Supernovas, and whoever else, and betray them.
-Status: Pending:
! Once the balance of power is askew with Whitebeard's death and the Supernovas, the remaining Yonkou, and independent New World crews heading to Raftel, the WG will summon all forces to prevent a second Pirate King from being crowned, Shichibukai included. Blackbeard will answer the call, and when the time is right, he'll stab them in the back during battle, make it to Raftel, get One Piece, and be crowned Pirate King.
I think that sums it about up.