Board Thread:Theories and Speculation/@comment-31099706-20180126164032/@comment-734582-20180127094737

Elveonora wrote: Well, Obito said 2 things, that he plans to 'sync' Sasuke with Gedo Mazo, which is likely the same thing that happened to Nagato and that Sasuke is ought to be stronger than Nagato in time, which heavily implies my aforementioned hypothesis to have been Obito's intention, which never came to be realized of course. I think you misunderstood my intent. Obito's plan was to use Sasuke for firepower. To me, it seems he was simply musing about the Gedo. So it wasn't really a plan, rather simply something he was considering. Sasuke had shown quite a bit of promise at that point after all. Yet it seems improbable to me that he would've been able to handle the Rinnegan at that point.

The synchronizing thing seems to be indeed the part where it pierces you with rods, and so granting the user that same power (the power to form black rods). According to Madara, whoever is synchronized with it can control it, so it seems that Sasuke would be Obito's pawn like Obito was Madara's.