But that's not him surpassing madara, as madara and he would be at the same level, but Sasuke would just be there longer....
To debate the issue further gets into speculation and hypotheticals... but f*** it, that's how this thread started. Time for a long bit of speculation that you'll probably disagree with.
I think awakening the Rinnegan requires an EMS and Izanagi.
The EMS user uses Izanagi. Most people like to point out that Izanagi takes the sight away from the the Sharingans, but an Eternal Mangekyo Sharingan can never have it's light dimmed. Danzo did not have an arm full of EMSs and he was never going to get an EMS because he wasn't a full blooded Uchiha anyway.
Since Izanagi requires Senju DNA, this tends to be a major barrier to awakening the Rinnegan, and Madara was power hungry. Waiting for a descendant that had Senju and Uchiha DNA wasn't something he wanted to do.
In the narutoverse, Cell implantation is probably a new process. This is why Madara didn't put some random Senju DNA into himself, and why orochimaru's research was actually ground breaking.
Harashima's Mokuton was unique because it generated living plants that were self sustaining to some degree, and that made obtaining a living sample easier then using cells from a different Senju.
The fact that Harashima was the strongest Senju and Madara's rival was just a bonus.
Anyway.... after obtaining the Harashima cells, Madara could use Izanagi.
Now at this point there's a bit of a Chicken or the Egg problem... Madara used Izanagi to create Gedo Mazo. I don't know which would come first; either Madara had the Rinnegan and that's why he created Gedo Mazo, or, it awakened in him when he created Gedo Mazo.
Regardless, at that point, I think the Madara's chakra was severely drained.
So severely drained that his crude Harashima graft went crazy. It probably wasn't a quick death, because Madara did have time to entrust Tobi with some key points of his plan and have his rinnegan implanted into Nagato.
Now, the reason why this is pertinent?
Sasuke has proven to be compatible with Orochimaru's cells. Orochimaru spent along time researching Harashima, and probably used his research and research material to enhance himself, meaning he's at least partially Senju.
If Kabuto implants oro cells into Sasuke, he'll have access to Senju DNA, which will give him access to Izanagi, and, possibly, the Rinnegan. It depends somewhat in what order the person gains access to the Rinnegan, however, Sasuke will naturally be surpassing Madara during his living years because his Senju Implant will be a perfected implant (perfected by Kabutomaru), instead of a rough Harashima graft.
If Edo Madara is not ended with the Edo Tensei technique, something to this effect will have to happen.
Someone has to negate Gedo Mazo. If Edo Madara can summon a giant Soul stealing statue, on top of being an immortal edo tensei summon, a rinnegan user with possibly 5 possessed kage corpses, and having access to his perfected Harashima graft, there would be no way to stop him.
Anyway... flame me. It'll be fun... actually... nm. I'll post up a thread for this spec all on it's own in the morning.
:hey: