First of all, these are two theories in one subject, and another theory on another subject, as in the rules, threads for theories are allowed, as long as they have a fair standing, which I think that mine does.
So, ladies and gentleman, you might be shocked at what I told you in the title, but in my opinion, Chopper and Robin are still not Straw Hats.
Let us look at all the SH's:
Monkey D Luffy: He's the captain, he's obviously a SH.
Roronoa Zoro: After the Morgan Ark, there is a chapter named "The First Crew Member" (Chapter 6)
Nami - After Buggy ark, she joins the Straw Hats and acts like a crewmember, however, she goes away later, and only comes back after having Luffy defeating Arlong, after that, there's a chapter named "Second Person" (Chapter 94)
Usopp - After Kuro ark, he joins the Straw Hats and acts like a crewmember, however, he defies the captain later, and only comes back after regretting what he did, after that, there's a chapter named "The Third and the Seventh Person" (Chapter 439) (More on "The Seventh" later)
Sanji - After Don Krieg ark, there is a chapter named "Member 4" (Chapter 68)
Franky - After Ennies Lobby ark, there is a chapter named "The Third and the Seventh Person" (Chapter 439)
Brook - After Thriller Bark ark, there is a chapter named "The Eight"
With this, there are Chopper and Robin left, and not one of them has a chapter name with their numbers (Member 5 and Member 6)
Robin is at the moment being with the Revolutionaries, while Chopper is in an island in which Birds rule the Humans, as seen in chapter 524.
Robin joins the Revolutionaries? Chopper allies with the birds and feels good being the ruler of humans?
Now, onto Dadan…
Let us look at the the page where he's mentioned:
http://www.onemanga.com/One_Piece/440/03/
Now, the mayor of Luffy's village names Shanks as "The Red Hair guy", so he doesn't seem to know much about him, even though he's a younkou and stayed about one year in the village he rules.
However, he knows the name "Dadan", as if it was something that was close to him. Which leads us to believe that not only does he have a connection with Luffy, as the mayor asked himself if Dadan knows about it, as he was in the village, because the mayor remembers his name.
What man could possibly fit in that?
As seen in this page:
http://www.onemanga.com/One_Piece/432/04/
Garp said that he had one friend to train Luffy and Ace in that village, and yet Luffy and Ace left to be Pirates.
This is quite obviously, at least to me, Dadan…
Dadan is the friend of Garp who trained Luffy and Ace, which is why he's known by the mayor (He was on the village training them), as he has some role with him (He trained them).
Here are my two theories, what do you think? Is there anything that supports or ruins them?