The Meaning of Proof
I sit here and watch countless people post about the tobi/madara topic and most of them end exactly the same way, In a stalemate. So lets try going at this question from a different angle. Sense the tobi=madara camp appears to be the largest out of the 3 main groups lets start with them. I would like the people that believe tobi=madara to provide proof that tobi is madara using the following guidelines. (I'll number them for reference later on.)
1. You cant use tobi calling himself madara.
2. You cant use anyone that tobi has possibly introduced himself as madara to.
3. You cant use anyone that is basing their belief that tobi is madara on the fact that he has controlled the 9 tails.
The reason for these guidelines are as follows.
*1. It's self fulfilling because there is doubt about his identity and tobi calling himself madara can not be trusted at all until his identity has been proven by a untainted 3rd party.
*2. They would fall under the tainted witness category because tobi has already told them he's madara.
*3. It is well known to us readers and the remaining uchiha that any uchiha with the sharingan can unlock the ability to control the 9 tails after certain conditions are met so the ability control the kyuubi is not solely limited to madara there for can not be used to identify madara.
There are the guidelines for the tobi=madara people I'll be adding the guidelines for the tobi=obito camp sometime tomorrow that way the tobi=madara has a chance to make their case b4 we hear the tobi=obito case