Here's what happened, to save you having to read those god-awful chapters 1) Kakashi Gaiden happens, Obito is crushed underneath a pile of rocks, says to Rin to take out his left Sharingan eye and give it to Kakashi. They then leave and all they know is they left Obito to die a horrible death either due to starvation or being crushed entirely under the rocks, instead of granting him a mercy death. 2) Somehow, the greatest coincidence of all time happens. Obito somehow survives, finds himself in a tunnel, crawls along for a while then collapses. When he comes to, he finds that the right half of his body has been operated on and replaced (but somehow his right eye survived). He finds out that an extremely old man saved his life, a man hooked up to a strange thing called the Gedo Mazou. A couple of Zetsu clones come in and after a while, the man reveals himself as Madara Uchiha (it was Madara or one of the Zetsu clones who had given Nagato the Rinnegan eyes, by the way, not Obito). 3) Obito stays there a while, a few months at least, while he recuperates. Eventually, one of the Zetsu clones goes out, comes back, says he saw Kakashi and Rin fighting off a bunch of enemy Jounin and ANBU. Obito then wears one of the Zetsu clones like a suit (that one's face is just like the Tobi mask). Obito goes out, only to see Kakashi killing Rin with his Chidori. Apparently he was tricked by one of the enemy Jounin. Kakashi passes out, but just before, both he and Obito awaken their Mangekyou Sharingan. 4) Obito loses it and with Zetsu enhanced strength and speed, kills all the enemy ninja. He brings Rin back with him (leaving Kakashi there). He says to Madara he will create a dream world with him, Rin and Kakashi in it. At the end of the chapter, he's now fully in his Tobi persona but introduces himself to Nagato as Madara Uchiha. I doubt Madara would have let Obito go completely carefree without any binding whatsoever... either he was under some genjutsu that made Obito see Kakashi kill Rin, or Kakashi was really about to kill Rin, and somehow Madara saw this, perhaps through the Gedo Mazou. Also, I don't think Obito falling into Madara's tunnel was a complete coincidence. Perhaps the genjutsu Madara could have put on Obito caused him to feel like he was falling into a tunnel, and he really just sent a Zetsu to retrieve him... We don't really know yet, but I think it would be way too corny if it was a complete coincidence. And yes, I agree with you, these last chapters have been absolutely terrible.