Who told you that I said that he copied it ? I said IT'S POSSIBLE knowing Tobi, since all his abilities are stolen or copied for god sake, stop making bullshit all over the place. Even if he did he perfected it or WHATEVER.
Yes, Nagato or Tobi can't pull up a techniques like Madaras meteor, which he did with smile on his face lol.
Yes Madara read FULL Uchiha tablet and nor Tobi nor Nagato did, and it contains all the secrets, nor Tobi nor Nagato knows about progressing beyond EMS to get Rinnegan I bet, also they don't know about Meteors and other stuff.
How he would counter ? His brother Tobirama I think was first one to develop and use strong S/T ninjutsu, he knew it, the weaknesses, the strenght and other points of it, he could think out the way, also his wife was strong Uzumaki with Insane sealing jutsus, that would also help him..