Gravity Falls: Is Dipper still Bipper?

Let me tell you a mistery from Gravity Falls. I hope everyone remembers the episode "Sock Opera" (season 2 episode 4). Well if you remember that, you surely remember that Bill used Dipper as his puppet, Mabel named Bill - inside - of Dipper Bipper. Well there is a theory that Dipper is actually still Bipper. If you don't believe me, here is the proof: in the episode "The Northwest Mansion Mistery", he walks with his hands on his hips, just like Bipper in the episode "Sock Opera" and then, when McGucket tried to warn Dipper that the end of the world is going to be in 23 hours,  Dipper just tells him to enjoy the party. In the episode "Not What He Seems" Dipper tried to stop the portal from starting back up, maybe he was trying to stop the portal from working because if the portal worked it would get Bill out of Dipper's body and Dipper back into his owne body.

I don't know if this theory is true or if the creator Alex Hirsch is just messing with us. I think I will go for the second option.
Characters featured in this Theory:

Dipper

                                                                                                                          Bipper



 
                                                                                

                                                  Mabel




  

                                       Bill Cipher

                                     
                           

                            McGucket